I know all advanced pterosaurs were quadrapedal while on the ground, but would Pteranodon ever do a pose like this? - https://www.google.com/search?q=pterano … =0ahUKEwjg

Everybody says no but wouln't it ever stand up on its two legs, flap and intiminidate an eneny?

The page you linked has many photos and I don't know which one you mean. But I would be astonished if pterosaurs didn't sometimes rear bipedally for threat displays: bears, gorillas and many other animals do it.