Hey @Pande! The way you can help the best in getting Crash Bandicoot over to Stadia is to reach out to some of the developers responsible for the game and express interest.
Here are the contact links for each developer:
Iron Galaxy
Vicarious Visions
Toys For Bob
Feel free to contact the publisher as well:
Activision
Sony Interactive Entertainment is also involved with the publishing, so Sony may be the ones in charge of exclusivity and which platforms it can be on. Although if you're truly curious about it coming to Stadia, I would recommend contacting the people in charge of the game with the above links.
