With F-Roa you can connect 2A after a corner throw. Timing is strict, about 1 frame or so. Out of 9 tries I succeed 1.
Characters with larger hitboxes (Wara, Nero, etc) are easier to connect.
Works on: everyone!
It's very easy on the Necos, and even 5A and 2B is possible with them.
You can connect 2A 5B -> aircombo or whatever you want,
except for the Lens, 5B doesn't connect.