Foley audio bank is just a data structure defined by BP. If you want to achieve complex surface effects, I think it is more appropriate to use chooser. After all, you have two dimensional inputs of surfacetype/NotifyEvent.
Although I have already implemented it, the problem still comes back to the audio engineering. The audio I found is not so high quality, and the Event variety is not so complete.
For example, Foley_fs_1p_sneaker_concrete_scuff_10, it’s hard for me to find sneaker on grass with matching quality, and I don’t know where to find scuff on grass.
A possible solution is to use audio software to mix?