Damn, I missed Beast's starters distribution 
No, but you can leave a Pokémon at the TGS. You chose your Pokémon, then select which Pokémon you'd like to get in return. If there's a player which meets the criteria (wants to give you the Pokémon you asked), the trade will be done automatically. It might take a while if it's an usual request or an unbalanced one (a Swirlix against an Yveltal for example).
Is there a way to look up what people will give up for something you n gts? I got z legendary available but can't find fair compensation
No, but you can leave a Pokémon at the TGS. You chose your Pokémon, then select which Pokémon you'd like to get in return. If there's a player which meets the criteria (wants to give you the Pokémon you asked), the trade will be done automatically. It might take a while if it's an usual request or an unbalanced one (a Swirlix against an Yveltal for example).