Yes, it works great. IdentityServer3 and IdentityServer4 are simply implementations that conform to the same protocol. The same applies to these average TokenValidation markers.
API AspNetCore, IdentityServer4.AccessTokenValidation , IdentityServer3 WebApi. , Asp.Net 4.x WebApi, IdentityServer3.AccessTokenValidation , IdentityServer4 AspNetCore. OpenIDConnect API, /, OpenIDConnect .