You can tell Hanna-Barbera's original Super Friends didn't have much of a budget. Everyone in the cast had to play multiple characters, and the animation coming out of Australia wasn't exactly on a par with the studio's output in the 60's. And that's with Alex Toth designing the characters!
Green Arrow was one of three 1-shot guest stars (Flash & Plastic Man were the others), and made his only SF appearance in the episode, "Gulliver's Gigantic Goof".
Edit, 2/11/19: The video has been deleted due to a copyright claim from an international rights holder.
The episode was a commentary on the population explosion, riffing at the same time on Jonathan Swift's Gulliver's Travels, except that in this case, Gulliver (Casey Kasem, doing a Peter Lorre impersonation) is a misguided scientist (and there were a lot of those back then) who thinks shrinking people will stop the expansion of the population.
Rating for the episode: A-.