Where else have you seen Trek sets, props and costumes? I'll start: The Mugato, sans horn, in The Lucy Show "Lucy's Safari"
A really strange recent example, Renegades: Ominara. It's much more Trek-adjacent though, being a spin-off/reboot of a serial-numbers-filed-off Star Trek fan film.
Janos Prohaska as "The Mikie" from the "Outer Limits" episode, "The Probe". Later reused as the Horta from the TOS episode "Devil in the Dark." The Calco alien from the Outer Limits episode, "Fun And Games". The Calco Alien mask (without its bulging eyes) and the taloned hands, were reused (with an added hairy bodysuit) in the Star Trek pilot "The Cage".
A scene was shot on the TRW campus for the Outer Limits episode "Cold Hands, Warm Heart," starring William Shatner. He'd revisit it later for the TOS ep "Operation Annihilate." Dem ol' rocks, in an ep of Have Gun - Will Travel: In Wanted: Dead or Alive: In Branded: And in the Airwolf pilot: And in the Rat Patrol!
Ambassador Shras' tunic appears in, and was likely made for, "The Conqueror" as one of John Wayne's costumes.
Cool! Wondering if the other costumes are re-uses, as well. Like that striped robe over Shras' shoulder.
Oh, dear. I hope it wasn't still radioactive. Oh, undoubtedly. They would've just raided the historical costume vault at the studio for whatever they could use.
In the alternate-universe episode of Friends (The One That Could've Been), Joey's penthouse had the same weird chair Worf had in his quarters on the Enterprise-D (and was first seen back in Season 1's Haven on the bridge of the Tarellian starship).