Kokak is a Filipino fantasy movie released in 1989 about a girl living in the woods who changes into a frog on certain occasions (I don't speak much Tagalog so don't know the plot in detail, just here for the TF).
GMA released a series in 2011 starring the lovely Sarah Lahbati, based on the original film.
The 1989 movie can be found here:
https://www.youtube.com/watch?v=RZqEc7G1wkc
It appeared on YouTube a couple times before and kept being taken down, so watch/download it while you can, you don't know what will happen a couple months down. TF is "poof" type and is very retro, featuring some drawn-on thunderbolts in one scene, but she does revert without her clothes on, so it's something I suppose lol.
The series, though more recent and better quality, is much harder to find. Here are some short clips of interest which feature TF (brief, morph type):
https://www.youtube.com/watch?v=Leb7gmuEhsI
https://www.youtube.com/watch?v=w4dVJngNtdM
https://www.youtube.com/watch?v=JncTWuTNVuw
I've hit a lot of dead ends otherwise for the series, so if anyone is able to find anything else on this, please feel free to share!