I just stumbled upon this article on fencing shoes today. It is a little bit outdated, written in 2011, but most of these models of shoes are still available. It also provides a nice overview of what fencing shoes are designed to do.
The Comprehensive Guide to Fencing Shoes
If you’re prone to foot problems, be sure to find a pair of shoes that is suited to your weapon’s style, your individual practice needs, and any previous fencing injuries.