I know I’m necroing this, but ran into the same issue with no answer anywhere and figured it out.
You can have pawns with crowd avoidance but it requires doing some C++ work. Crowd avoiance doesn’t work out-of-the-box with pawns because it requires the movement controller to implement IRVOAvoidance interface, which pawn and flying pawn movement do not. If you look through the crowd control code you will see that it uses that interface to know which group to avoid and which to ignore and if there is no interface all values are 0 hence it doesn’t work.
Search for /** BEGIN IRVOAvoidanceInterface */ in CharacterMovementController.h, copy the function declarations from that block, copy the implementation and variables needed, modify the function calls which use capsule component to suit your implementation and don’t forget to public IRVOAvoidanceInterface extend your controller class.