advice on edgeguarding ike squirt and roy?, ike has hitboxes that cover the ledge by the time he pulls himself up(unless i'm timing it wrong), squirt i can kinda bair but it's pretty difficult, roy has long lasting hitboxes and kinda floats near the ledge
For Roy, what I usually like to do is look at his positioning, and if he's at a point where he's pretty much forced to sweetspot the ledge, you can do a full jump and then steal the ledge before he can grab it. The ending of Roy's Up-B has about 12 to 13 frames on the end of it with absolutely no hitboxes whatsoever, and he can't grab the ledge until the animation for his Up-B is completely over, giving the opponent a feasible amount of time to actually get to the ledge before he does.
If he goes for the high recovery, whether it be because you tricked him by fooling him into thinking you were going to take the ledge, or because he's trying to land on some sort of platform, you have Up-Smash (though you should use this only if it'll kill him) if he's planning on landing on the stage, and Down-Smash and Forward-Smash if he tries to drift back to the ledge. You could also go for a back-air if he's high, just make sure that his animation is at the point where the hitbox isn't there.
For Ike and Squirtle, I'm just making theories here, as I don't have that much experience with either of these matchups. It's something I hope to change in the near future.
For Ike, you can try to stuff out his side b recovery with either PK Freeze or the tail of PK Thunder. If he uses Quickdraw to try and sweetspot the ledge, you can use Lucas' down smash (preferably OU Down Smash).
If Ike gets a walljump from his Quickdraw, you already know the Up-B is coming right after. At this point, if he's recovering low, you'll want to wavedash to the ledge as he's about walljump and then use Up-B. A neat little trick with Lucas (and other characters with a Z-tether) is that if you grab ledge, immediately hold back on your control stick, and then press Z while still holding away from the ledge, you'll tether the ledge very quickly. What makes this interesting is that if you immediately reel in after the tether connects, the invincibility from your first ledge grab will last the entire time during your tether reel, preventing you from taking any hits of Ike's Up-B. You also get more invincibility from grabbing the ledge that second time. From here, you can roll off the ledge and laugh as Ike plummets to his death.
For squirtle, his Up-B has hitboxes in front of him, with a giant hitbox in front of him at the end of the attack, so really your only options here are to try and get a Down-Air from directly above or a Back-Air. If Squirtle opts to recover to the ledge with Side-B I guess you could try an F-Smash or a D-Smash.
Hope this helps. As I said, the examples for Ike and Squirtle are just some theories of mine that I'll have to try out in the future. I've done the Roy edgeguards multiple times before. Obviously, nothing is truly set in stone here as long as your opponent is good at mixing up recoveries. Sometimes you'll have to go for the unconventional options to get rid of your opponent.