I have personally rest countered Bowser Bomb, sonic's spin dash, Zelda's Faore's Wind, Rollout,
's
, yoshi's ground pound, Falcon Punch(although it's much easier to just duck under it and hit
as it's above us if we're on the ground), Flare Blitz(one of the harder ones), and falco's
(haven't landed it on fox but should be just as easy.)
Falcon Punch, as I mentioned, is usually just easier to duck under rather than trying to directlly counter it, spindash and clown car dash can be good to rest counter once if you know your opponent isn't expecting it, but past that it's too risky. Bowser Bomb and flare blitz don't attempt unless you're absolutely sure you can get the timing down. Yoshi's ground pound is also dangerous to try rest countering but it requires a little higher % before it'll KO.
Zelda is also a tricky one to try and rest counter as if she fakes you out and doesn't teleport at you, gg. otherwise,
you should be able to counter KO punch too but it's bound to be trickier.
Don't try countering Shoryuken, both puff and Ryu have invincibility frames so Ryu will live, but you'll still die thanks to the endlag. Or maybe Ryu has super armor, I forget if the startup frame is invincibility or armor, either way you won't kill him trying to counter Shoryuken.
As mentioned, most likely any attack without a disjoint can be countered with rest as long as you know the timing.
