did you try these already https://itch.io/games/tag-coming-of-age
you can refine with other tags like story rich, or genres like visual novel. but it is only about 10 pages of such games, so you can glance over all of them in a few hours.
which leaves the games that did not use this recommended tag. maybe you see related tags on the coming of age games for other games that have similar topics but where the publisher did use different tags to describe the same.