There isn't one, but you can turn off various hentai, mature, nudity, NSFW, and sexual content tags. Most of the RPG maker games have the Hentai and NSFW tags (but that includes Neptunia x Senran Kagura). And then bookmark the link for quick reference.
gog.com/en/games?tags=jrpg&hideDLCs=true&excludeTags=hentai,nsfw
Messy, but you'll be missing out on some good non-RPGmaker games if you disable the other 18+ tags:
- Mature - Akiba's Trip series, Hyperdimension Neptunia U, Yakuza series
- Nudity - Agarest series, Death end re;quest, Dragon Star Varnir, Hyperdimension series, Neptunia x Senran Kagura, Ruined King, Yakuza series
- Sexual Content - Akiba's Trip series, Death end re;Quest series, Dragon Star Varnir, Fairy Fencer F, Haven, Indivisible, Megadimension, Neptunia Virtual Stars, Yakuza series
I agree though, GOG needs a separate tag filter for RPG maker games.
Post edited November 25, 2023 by UnashamedWeeb