Now that there's no dumb loop that takes out all of your life for making one mistake, I find this matchup much less stressful, actually kind of fun.
Be patient at first and don't rush in...don't jump predictably or you can get nailed by his iad fastfall grab. You can poke Ada with jump cancellable moves and react to what Carl does. So you can do something like 3C, jump away, or 5A xn, 6A if he jumps towards you, jump away if not. Or 5A, 3C if he attacks from the ground, etc. Of course he can bait this with Ada's moves with super armor, you can still stop her by gatling into more moves and possibly hit Carl if he's close enough.
If you get sandwiched, definitely Burst/Counter Assault/ID rapid out of there asap (it looks funny to ID Ada really quick then fly away). Heck if your ID CHs Carl you can go into combo and practically gain the heat from the rapid back. I think I saw Spirit Juice do something like ID CH Rapid, dash 2C 5D double BE combo for around 3k. His j2C isn't an overhead anymore so it's a lot easier to block his stuff but his mixup is still ...j2C is still a great crossup, pay attention to his distance from you on JC-able moves.
When you get in on him, try not to let him go...burn up RCs to get past his guard if you must, since you'll take out a ton of his health or at least get him to burst. He only has like 4 primers so a using guard breaking moves isn't out of the question either (2D Rapid mixup or Dead Spike rapid mixup are nice).
If he tries to Fueco on your wakeup to get you to guard, you can roll in the other direction. I imagine a better Carl would try to use something to stop you from rolling though. Even if you guard it you can mash back to IB the hits and gain some extra heat, could be enough to get you a CA.