There are a lot of bugs and tricky aspects to some monster skills, and often we can only learn the hard way by losing battles.
It would be nice if we could set up a test battle for PVP, where we simply place any monsters as opponents and can try out various combos from our monster list.
This way we can experiment with what works best for us, as well as help us to run tests and analyze any potential bugs that may occur with any skills or monsters.

I like that we can do a test battle against our own teammates during team wars, so perhaps doing something similar would not be too hard to put it into pvp section?