Its_A_Random
A distant memory
Initially, it is decided by ID, but according to this Smog Article, you can dictate what sort of shop you open up when hired by other users through the use of Ace Trainer Future, i.e. The assistant that tells you what sort of shop would be a good idea to open.what of npcs that are representations of the player character of another? is there specific criteria as to what they can give out, or is that determined by their trainer id or something?
Also, talking about the E4 Solo run question, if you managed to get the event for it, SubCM Keldeo with Substitute/Calm Mind/Surf/Secret Sword & an EV spread of 4 HP/252 SpA/252 Spe is a solid choice — That is what I used to get that medal anyway... But odds are you prolly do not, so it is not exactly a good choice in terms of availability.