Manimal had an interesting premise, but really needed todays CGI.
https://en.wikipedia.org/wiki/Manimal#Overview , https://www.youtube.com/watch?v=Trze_WGSjZo
https://nbc.fandom.com/wiki/Manimal , https://www.youtube.com/watch?v=7cCdvAtS1co
Maya was a character that was seen on Space:_1999 several years before Manimal.
https://hero.fandom.com/wiki/Maya_(Space_1999) , https://www.youtube.com/watch?v=ZKiIYvWIUj0
https://catacombs.space1999.net/main/cguide/uccm.html She could turn into a mouse or a monster, or just about anything.
https://en.wikipedia.org/wiki/The_Metamorph , https://www.imdb.com/title/tt0706350
https://en.wikipedia.org/wiki/Space:_1999#Series_3_(cancelled)
https://en.wikipedia.org/wiki/Space:_1999#Compilation_films
https://en.wikipedia.org/wiki/Space:_1999#Revival_attempts_and_audio_dramas
With today's level of CGI, there easily could be a Space: 2099 movie and a HuManimal movie. Updated versions, but with some of the original aspects.