Yes, this was "inspired" by TSM Zero's video for Sm4sh characters, but I felt like it would be appropriate for SSF2 to have a similar discussion.
I made strats based on what kind of playstyle the character's meta represents, like combo-heavy characters being countered with Mixups, and the best way to defeat their recovery and knock them off screen.

Gimp him whenever possible. Respect his special moves, and don't underestimate his down-B.
Don't underestimate his smash attacks. Stay out of command-grab range. Reflect any projectiles he sends to you. Try to send him upwards, and gimp him if you can.
Avoid his bombs, and try to send him sideways.
Don't let him land. Reflect his projectiles and avoid his command-grab. Try to send him downwards.
Avoid Falcon-Punch reads. Use a lot of mixups. Send him downwards, under the stage if you can.
Try to send him upwards.
Learn how to airdodge. Don't get grabbed. Out range him if you can. Send him downwards. Don't let him land.
Use a lot of mixups. Duck under his projectiles. Send him downwards. Avoid using projectiles.
Pretty much the same as , but don't underestimate his smash attacks.
Avoid his downsmash. Counter his Dair with utilts and usmashes. Stay away from him in Kaio-Ken. Send him upwards.
Avoid using projectiles. Avoid his Dair, Side-B, and jab. Send him upwards.
Reflect his projectiles. Use a lot of mixups. Don't underestimate any of his moveset. Send him downwards.
You're on your own.
Stay in the air, but don't try to trump her aerial game. Avoid rest setups, and don't get grabbed. Most moves will kill her at earlier percents than normal.
Umm... have an IQ higher than 69? Also don't fight 3 at once?
Avoid his smash attacks and aerials. Use his projectiles against him wherever applicable. Send him sideways.
Try to outrange him. Don't underestimate any of his moveset. Send him downwards.
Don't let misfires catch you off guard. Punish his dash attacks. Send him downwards. Respect his aerial game.
Also on your own.
Stay on stage. Send him downwards, under the stage if you can.
Outrange him if you can. Use plenty of mixups to avoid counters. Don't stay in shield for long periods of time. Send him downwards.
Don't underestimate his moveset. Send him sideways.
Take every opportunity to gimp. Figure out which moves have more priority than his tornado and drill attack. Don't let dimensional cape catch you off guard. Send him upwards.
Just watch your step. He leaves sh!t everywhere.
Reflect any projectiles he throws at you. Gimp him wherever possible. Send him upwards.
Avoid or grab his projectiles. Use his trampolines against him. Maintain stage control. Send him upwards.
Don't underestimate her moveset. Avoid or grab her projectiles. Use mixups to avoid counters. Don't get downsmashed. Send her downwards, under the stage if you can.
Use a lot of mixups. Avoid his down-B. Send him downwards, under the stage if possible.
Gimp him when possible. Respect his projectiles and side-B. Avoid using projectiles. Send him sideways.
Respect her aerial game. Interrupt her charge shot. Avoid her charge shot and bombs. Send her sideways.
Just... I don't even know.
Interrupt any attempt to switch. Use a lot of mixups. Send her downwards.
Avoid Uair setups. Send him sideways.
Trick him into SDing. Use a lot of mixups. Don't underestimate his moveset. Send him downwards.
Have patience.
Avoid his side-B. Send him downwards, and keep doing it.
Lets wait until after the update to give him a definitive strat.
Don't underestimate her moveset. Interrupt any attempt to switch. Avoid her all together at high percents.
Keep her off the stage. She'll SD eventually.

Let me know if I missed anything, or if there's a way to improve these strats.

Staying in on (besides the not letting him land part) is very good way to end him quickly, just as long as you know what your doing (like combos, and finishes).

I guess lol.

watch out for dairs and go in on him quickly when he lands it on stage.

(this one is probably just me), predict where he will land after he teleports or where he might teleport to.

get him off stage and keep him off stage.

They won't be switching often anyway, but you shouldn't interrupt switches. You should punish them.
Keep in mind falling command grab, especially as he is recovering. Beat him with persistent hitboxes, disjoints, projectiles, and intangibility.
Avoid and punish crash bomber when you are invincible.

One thing I made sure to consider is what recoveries are really messed up by the stage.
One of 's key differences from is his recovery. 's up-B goes diagonally, while goes straight up. Because of this, has a harder time recovering than , especially if is already right under the ledge. He winds up running right into the stage, and then falling down without gaining any vertical momentum.
Characters with this problem include , (but not as much), , , , , , , (thankfully), , (also not so much), , and . It's important to get these characters under (and I mean UNDER) the stage when trying to kill early.

Well, technically it can be angled to go almost straight up, but whatever

Spam disjoints

Wait i'm curious, what stage messes up recovery when he has 5 jumps and a couple moves to help boost him back on stage?

Utilise projectiles to make him drop his bombs before he has the chance to use them against you.
Send him sideways and make sure you take his jump (horizontal recovery is weak).
Respect The Sweetspot Dair: https://streamable.com/o0nys .
Always tech/tech-roll to avoid his Jab Lock to Up/Forward-Smash (which kills pretty early), Down-Air to Up-Smash and his Down-Throw to Up-Smash finishers. Watch for wavedash to (pivot) grabs. Don't challenge the U-Air, if possible, stall in the air and land safely. Don't challenge the D-Air- just don't do it. 's main means of a horizontal recovery is via F-Air + Neutral-B (for momentum forwards) and finally a Side-B to the stage: Only challenge this if you are able to send him downwards, otherwise reflect/perfect shield the Getsuga and if does not use Side-B to sweetspot the ledge, grab and throw him back of the stage (or use a smash attack to kill because of the landing lag if is at kill percent). Uhhhh, that's all I'm saying about my main

For just attack his arms/legs when he attacks, it extends his hurtbox. But be careful and do get to close when he attacks.

With the concern is more gimping him until he has no more jumps left. If you can push him under the stage in this process, you don't necessarily have to push him away, as most gimps usually work. But I get your point. In the end, it's probably more effective to just push him away.

Beating...

Watch out for his surprising tech-chase ability and don't recover low... at all.

Play Jiggs if you're feeling ballsy.

Don't play Bowser. If you must, It's called FH Fair, Fair, Rest. Isai that s*** for your own sake.

/ Get 'em offstage.

Personally, I prefer the Dair.

They're called 'moves with any range at all'

EDIT: a bit more clarity

How does one perform an Isai?

Don't get hit.

lmao bruh

Isn't Isai that one guy from the 64 days who would sandbag in tournaments, even though he was arguably the best smash player that ever lived?

Yeah, and in Smash 64 Puff did Fair -> Fair -> Rest a lot.