@Strangeghoul17 I wouldn’t worry too much about it. Unless you rip it off wholesale and exactly, it’s not protected. Also you’re looking at FF12 which was as far from ATB as the series ever has been (Excluding FFXI and FFXIV which use RTB).
I think you should continue down this path, and once you get near the end, figure out how you plan to make it NOT FFXII. 
Plus, nobody likes things to be TOO exact. Sonic was intended to just be faster Mario but as we saw it was different enough to still be very distinct even though they both focused around moving right and jumping.
In other words, don’t wholesale copy it but put your own unique spin on it. It’s very very hard to argue that a mechanic is the exact same- Mario Jump =/= Sonic Jump. Don’t use progress bars based on a speed stat and you’re fine. AI combatants has been done many times, Square Enix is not going after LoFi games for Kenshi, after all.