DiVA has done Blue rose and MARIA.
Watarirouka has done Pajama Drive and Hatsukoi yo, Konnichiwa.
Not yet has done Nakinagara Hohoende.
French Kiss has done Kuchi Utsushi no Chocolate and Temo Demo no Namida.
And No Sleeves also did Bye Bye Bye and Junai no Crescendo on their album but that probably doesn't count since Miichan, Harunyan and Takamina sung the original version too.

Quickly checking generasia it also looks like No Sleeves did Gyakuten Oujisama and Hoshi no Mukougawa.
Might have missed something since I'm not that familiar with the older single B-sides of the sub groups.
