Sonic is especially adept at being nimble. I'm not gonna say he's danmaku-dodging level, but his forte is being fast and applying it to avoid attacks. Case in point, him dodging the attacks of several characters at once and him running in between raindrops to stay dry. There's probably a few other things, but I'm lacking scans arm.
It’s also impossible to reach speed the light yet a bunch of characters are faster than light. It’s just one of those things that defies real life logic. Did Sonic make himself flat while avoiding the rain drops? Eh, probably not worth trying to make sense of it.
Invalidating a feat because it doesn't make sense isn't good for countering an argument. It's fiction, things that don't make sense are commonplace. Difference between lava and rain is that rain actually has some distance between each drop, be it small or not. Not everything will add up.
Sonic can just as easily turn himself invisible, and her Danmaku doesn't seem to home in on a target (if it is, Homing Attack needs to be added to her page). It'll be especially easy to do so if he turns invisible. If Sonic knows he can't dodge it, he'll turn intangible or invisible since either can work depending on the scenario. He's a combat pragmatist, he isn't gonna try and dodge something so blatantly nigh-unavoidable.
Outdodging molecules isn't equal to raindrops. There are such larger spaces between raindrops than molecules that it's sort of a joke to compare them. Point is that Sonic dodged rain, not much to be said. Whether it's bs or not within reality doesn't matter, the feat happened.
I'm not gonna claim it's invalid because it isn't on the profile (since that's just a stupid argument imo), but it's best to get Homing Attack on there.
Sonic still has Chaos Control, which he often uses during extremely difficult or bleak encounters when he has a Chaos Emerald on his person. He can loop back time by a few moments (such as ten seconds), can slow it or stop it altogether to make things a lot easier for him, and can teleport to get himself out of a tricky situation. If there was ever a time he'd use it, it would be here.
Power Rings are also a thing, which can BFR to other dimensions and have 2-A Power Null (both of which are thought-activated). Sonic has often lead with BFR with them, such as when he was in a fight against someone (I forgot who) that him and Tails couldn't beat. A few other occasions as well.
Couple that with Sonic still being able to take a good amount of attacks even if he does get hit due to Damage Reduction alongside his Instinctive Reaction (that's constantly slept on lol), and you have several ways Sonic can avoid attacks, counter, stall for time (or stop it), and outright beat Remilia. All without discussing Fatehax.
Basing from experience in Danmaku if you dodge at the wrong side you basically cornered yourself to get hit so dodging it isn't gonna always means you get out unscathed specially if you don't plan out your dodging and dodge by instinct at the very least you'll be grazed. also dodging something that is on the same speed as you is harder to achieve lets just assume that since speed is equalized sonic has to dodge raindrops that has the same speed as him and pair it with homing attack.
BFR and powernull is still easily a wincon for sonic
atm Sonic still has more chances of winning still
Voting for Sonic