If I were Erdogan I’d invite him and if Putin did come (which I’d doubt) I’d arrest Putin and bargain with the US and EU for more favorable treatment. I doubt Russia would DO anything other that have the next strongman talk about how stupid Putin was and withdraw back to post 2014 borders. Even just a “whoops my bad” kind of reaction and immediate withdrawal sans Crimea would probably take the wind out of the sails of Western support of Ukraine since the threat of genocide and further annexation would end.

Erdogan might even repair the damage to his image that came with mishandling the earthquake. Or get enough people forgetting about it that he maintains power.

This will never happen, but if Putin were dumb enough and Erdogan bold enough… the legal authority is there since Putin is wanted for war crimes.