No, refection system only supports UObject based classes, other classes won’t be visible to UE4.
But there work around depending on what you trying to do, structs. Structs in UE4 can only use UPROPERTY, but on C++ side of things structs work same way as class, you can not use UFUNCTION… but you can still make unregistered functions on C++and you can always do nodes for that struct via static functions in some UObject.
The only issue is fact that you can not use struct pointers in blueprints, as most you can use references and when you set struct you just create create copy of data.