Re: Smallville Season 11, it"s happening...
In "Smallville" though, all we got I think is a couple of CGI shots of J'onn in his costume, not in Martian form though.
We briefly saw him in his native form in "Absolute Justice" when he regained his powers via Fate's Mars portal:
"Of all the souls I have encountered in my travels, his was the most... human."