That would be a Variable Power Pool limited to "Mental Powers Which Belong To Minds Copied Via (power x)". I see (power x) as Telepathy, but a large cosmetic Transformation could work also (person with an organic mind to person with a copied organic mind). The GM could allow you to buy the copied mind as a computer via the VVP.
Sounds like a limited Telepathy only with copied mind. If I was a GM, I would probably instead have you Mind Link instead.
Again, if you want to compel an answer, I would say Telepathy. Note, Telepathy does not compel the copied mind to answer truthfully.
For the mind itself, a VVP which you can buy copied minds as Computers, with the GM's permission. A Multipower for communicating with the mind and generic things a copied mind gives you (regardless of how strong or weak the mind is). Because of the VVP, you will only have a limited number of minds.
Special note: Computers do not have Body, so they don't have a normal physical form (the body is usually bought as an automation). Check with your GM before you buy the powers.
"Mental Duplication" is the special effect. What does this allow him to do? Sounds like Telepathy with Invisible Power Effect, a bunch of Skill Levels, strong Mental Defense, strong +MOCV and +MDCV, and Photographic Memory, at least.
