Season 2 came to an end with the announcement
Episode 12 of the ISEKAI QUARTET2 anime aired today, but this doesn't spell the end for the crossover comedy. As revealed at the end of the episode and via the anime's official Twitter account, there's another season in the works for the ISEKAI QUARTET series.
Here's the image that went along with the announcement:
Directed and written by Minoru Ashina (Isekai Quartet, KAIJU GIRLS, Lord Marksman and Vanadis ONA), ISEKAI QUARTET brings a bunch of different isekai anime characters into the same class together, including some from Overlord, KONOSUBA, Re:ZERO -Starting Life in Another World-, and The Saga of Tanya the Evil. Season 2 introduced characters from The Rising of the Shield Hero, so we'll have to wait and see what season 3 has in store.
Source: ISEKAI QUARTET episode 12, Twitter