So Sonic plays quite similar to Squirtle. Just need to adapt to the different tools. Instead raw speed in dd/run, Squirtle abusing the weird turn around (as you know). Most of it is pretty intuitive, but here's an example anyways. You land a spaced bair on shield. You dash away expected them to retaliate with a Nair. This whiffs and you immediately shellshift hydrograb and zip in and grab them. There are lots of situations like that where because they have less options, you can bait and abuse your burst speed.
Other non-hydro stuff. Dtilt is great. Like a Roy dtilt (interupt on frame 23). First hit can always be asdi'd down and shield before the second hit, be wary. Safe on shield, combos almost always, and its quick (frame 3).
Bubble is your go to anti cc option. Puts them in a trip tech situation. Also safe on shield when spaced. Tech chase with it. Also deals with dis joint quite well. Only loses to projectiles (can't clank) and preemptive jumps. Also slows you down a bit. If you have good reaction speed, try working on reaction tech chasing. Its great.
Our initial dash is really short (like sheik), so crouch out of run dtilt/bubble is really good. Most tail attacks have intangible tails during strong hits (up air, back air, down air, f tilt, D tilt,). Nair has a low angle (30?), dair stuffs most verticle recoveries, bair does most horizontal. Water gun is like sheik needles. Leads to grabs when close, off stage is really good on horizontal stuff. Withdraw is safe on shield. Uair into up b is pretty good. Weak up air (the back hit) has a 90 degree angle and is weaker, so it into aqua jet is amazing.
That's most of the raw little things. Otherwise just slide everywhere and do stuffs.
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