In ouliner search ‘navm’ and you will find your navmesh and recast objects, select recast objects and check ‘Enable drawing’. In mavmesh bounds check all supported agents. Now they should show up. As for selecting agent it selects automatically an you can’t do it manually, selector choose agent that have MORE OR EQUAL radius/height than your pawn, but thats not all, there is checkbox in character ‘Update Nav Agent with Owners Collision’, try to uncheck it.
These agents look so underdeveloped, i’m trying to make manual selection. Mav be ‘Preferred nav data’ supposed to do that, but it does nothing.