I found Lake shoes has the best options for toe box room. This will get you started but you will have to see if the style of shoe comes in the desired width. Lake has a table to help. You may not find a shoe width a sole flexible enough for walk in the desired width. If you are close to an REI they stock some shoes you can try on. There web site will let you know of the show in a specific size if in stock at the store. It takes some looking.

https://www.lakecycling.com/?https:/...0aAkVTEALw_wcB

Most likely their mtb shoes will be the best options. They have a sandal. Not cheap.

MX-169 looks like you best bet. If Lake does not have it check or others online. They can be hard to find in the size needed.

https://www.lakecycling.com/collecti...roducts/mx-169