Honestly, this may be for the best. Unless you were using it for a vehicle or world map segment, I'm not sure using mode 7 with an active battle system would be... a very solid foundation for gameplay.
ABS systems require that the user be able to accurately judge distance between objects in constant motion; Mode 7 effectively warps half of this information given to the player by drawing everything in two perspectives; a "3D" perspective that is an angled view of the 2D tileplane, and the event plane, which draws characters, events, etc. but gives them additional depth via the z-axis. This gives the illusion of objects in the event layer popping up in three dimensions, but also distorts a lot of the visual information that relays speed and depth.
Long story short, using the two together in any kind of scene that involves combat could be a headache for the player. It could very well turn-out to be just fine for the player after they get used to it, and it's a cool idea, but unless you're making a tech demo, gameplay considerations should come first.