No other details announced yet. This announcement comes as the finale for season 1 aired today. Check out the Crunchyroll article for additional information. Synopsis for the first season from AniList:
“I have no interest in real girls!”
So claims Okumura, the president of the school’s manga club. He’s your typical otaku, obsessed with a sexy (fictional) 2D manga character known as Lilliel. Then the new school year starts, and a (real!) 3D girl named Lilysa whose passion is cosplay joins the club. Lilysa convinces Okumura to become her photographer–and guess who her favorite manga character is? Not only that, but Lilysa is into modeling the fetishy stuff! The boundaries between 2D and 3D start to blur as this hot-blooded romantic comedy unfolds.
My Dress Up Darling... Again?
Similar premise, but quite different. Aside from a pretty different cast, My Dress Up Darling focuses more on how to cosplay (particularly with regards to the actual outfit and makeup), and this one more about the culture surrounding cosplay.
Ah, I see... I mean, frankly speaking, there are so many isekai with practically the same plot, that I don't mind this at all.