I would even say that "hyper" by itself has tended to mean endowment size. You can then expand (ha) out, with hyper-muscle, hyper-fat, etcetc. But I would not make the connection that "hyper" by itself means muscle.
Here are a few of the hyper artists that I know A-side! And yes, most artists that do hyper here on FA mostly do hyper muscle, but they have done other bouts of hyper proportions as well. Hope these help!
https://www.furaffinity.net/user/aru.beru/
https://www.furaffinity.net/user/canon15/
https://www.furaffinity.net/user/centaurus/
https://www.furaffinity.net/user/danuelragon34/
https://www.furaffinity.net/user/flag/
https://www.furaffinity.net/user/hungothenomster/
https://www.furaffinity.net/user/juano/
https://www.furaffinity.net/user/lromstar/
https://www.furaffinity.net/user/regnar/
https://www.furaffinity.net/user/takataka/
https://www.furaffinity.net/user/uniparasite/
https://www.furaffinity.net/user/wolfiecanem/
https://www.furaffinity.net/user/zerozero/
Not sure what you are looking for exactly but here you go . Good luck
looking for artist who are fine doing gals too and male characters with proportions like these: https://www.furaffinity.net/view/40552394/
https://www.furaffinity.net/user/bobert/
These two I typically think of for hyper
https://www.furaffinity.net/user/silver-stag
https://www.furaffinity.net/user/tankh
https://www.furaffinity.net/user/danuelragon34
https://www.furaffinity.net/user/bambinewsted
https://www.furaffinity.net/user/rottweiler
https://www.furaffinity.net/user/kartos
https://www.furaffinity.net/user/goroguro
https://www.furaffinity.net/user/guzreuef
https://www.furaffinity.net/user/clock-face
https://www.furaffinity.net/user/ectogoat
Well hyper is no stranger to me, as for action, I can always try more of it if given the chance.
examples:
https://www.furaffinity.net/view/26692224/
https://www.furaffinity.net/view/27163334/