New Game! features a cast of cute adult girls working at a game development company, while Stella no Mahou focuses on cute high school girls who are in a club that makes doujin (self-published) games. Both shows, while primarily focused on the cute girls, give some insight into the process of making and selling games.
Stella no Mahou is basically 'Amateur's New Game!'. By that I mean that in New Game!, one followed an adorable all-female cast of professional gamemakers on their way to a new title from the perspective of Aoba, who was new in the industry, whereas in Stella no Mahou, one follows an adorable all-female cast of highschoolers that want to make their own game from the perspective of Tamaki, who has little to no knowledge about making games.
I'd see this anime has many similarity in source, genres, and it's theme about game making. And both have not male chara too
Somethings differ is New Game! Are much popular than Stella no Mahou in both anime or manga and the characters average age.
Token recommendation as these two are probably the closest to each other out of the CGDCT pack, much more so than the show that has the highest rec count for Comic Girls at this point(April 21 2018), which is New Game
Both Kirara, similar subject, not identical but comparable relations/dynamics between the main cast, and a slightly serious/coming-of-age tone towards the main character
There is of course here the superficial aspects that make these series similar. Groups of high school girl making crap. Much more similar to each other in tone, setting, and comedy than either is to New Game, for example.
The reason I've gone out of my way to link them together is they are both major examples of an incredible female lead trapped inside of a bad anime.
They have the same feeling of Cute Girls doing Cute Things. But most important both deal with one of the girls (both shows focus on girls) as they discover something new and their feelings surprising people who already do what the are learning - probably regaining some part of wonder that led them to begin with. (in this case camping & making a video game)
Both also have some degree of comedy.