…The goal says Spider Man and Spider Gwen are needed but the special rules on Miles Morales say he counts as a Web Slinger.

A: If he says he counts as a Web Slinger, then that’s explicitly telling you YES you can use him to substitute for either of the two listed on the Goal. So it would be as if the Web Slinger Goal said “any two out of three of: Spider Man, Spider Gwen, Miles Morales.