So, I’m sure there will eventually be a master list somewhere, but I went through all the Gen 1 Pokemon to see what a second move costs. To be honest, some of the values are sort of baffling and feel almost arbitrary. lol
Legendaries and Mythical cost 100K stardust, so I left them out. I went through every Pokemon whose final form was in Gen 1. Scyther, for example, evolves later so I counted it now.
For the sake of space, I will list the 10K and 75K. The 50K list is HUGE!
Everything else is 50K.
Some of these make a lot of sense, but others are odd choices. Farfetch’d, for example, costs 50K to add a second move. I don’t see anyone doing that. The Gen 1 starters and Gyarados cost 10K, which is kind of a steal. Jynx, the Hitmons, and Onix cost a whopping 75K though!
UPDATE: Just went through Gen 2. Even more baffling.