I’ve seen a lot of concepts, a few brought to market. Nothing successful. I think it is one of those things that is better in theory than in practice.
Footwear is not something that is that expensive if you want to have different styles to complement different looks. The practicality of limiting design by modular elements (ie. can’t change outsole or last shape) and the complexity of having to swap parts out and compromise on design to allow for some sort of mechanism accordingly make it a non-starter.
R