I gleefully volunteer Avan for fellow teen friendship. His two closest people back home at this point are a princess and a guy with super strength, so he is well-equipped.

Getting a memory from someone you haven't met before could be an interesting way to get a first impression! Is there one of Dimitri's that you think would be especially good for that? What would be most interesting to Avan would be one with Byleth since he knows that his own future self is a teacher but he isn't clear on why he chose that career path, but then that's not likely to give a strong impression on Dimitri, is it?

Alternatively Dimitri get one of Avan's?