Since Tesla introduced the ability to plug in a game controller for the on-board games, the search for a decent compatible controller (that works properly for Cuphead) has been on. Fortunately I can recommend one that works perfectly and should be readily available.
The Microsoft Xbox One ‘PowerA’ controller
This is what I have in my car, works as expected (although mainly just sits in the centre console!)
Available from GAME, Argos, eBay and Amazon
Other accessories
Visit the Accessories category to see other must haves for your Tesla