Auto populate custom form in a request from another existing project

When submitting a request a user can select a project that the request is related to. The request has the same custom form on it as the project that is being referenced. Is there a way for the information on the custom form to automatically import into the request so that the requester does not have to fill in all the details again? I thought about trying to use Fusion but this wouldn't populate the information on screen for the requester.

Any suggestions would be most appreciated