Verifying patches means owning the games, which while I would love to own every lewd Steam game, is not practical for me at the moment.
If you have an interest in helping me out with game access, get in touch through the contact page!
The uncensored version can be bought from the MangaGamer store.
An unofficial uncensor patch has also been made by ItaloKnox and posted over on Github. An addendum to this has also been created thanks to Kimchi Tea that allows the content to work even when launched directly through Steam. The links and information provided here refer to this unofficial patch.
In order to revert to the all-ages version, modify "persistent.adult = True" to "persistent.adult = False" in both the "adult.rpy" and "defines.rpy" files.
When you open the game, a warning about adult content is displayed. Additionally, the title will just be MYTH, instead of MYTH (all ages).
Steam store: https://store.steampowered.com/app/366380