Here is the full list of all 32 Elemental Girls achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Gaia Easy
Agnia Easy
GameOut
Genevieve Easy
GameOn
Genevieve Normal
Genevieve Hight
Agnia Normal
Agnia Hight
Gaia Normal
Gaia Hight
Hera Easy
Hera Normal
Hera Hight
Korentine Easy
Korentine Normal
Korentine Hight
Pelagia Easy
Pelagia Normal
Pelagia Hight
Lesma Easy
Lesma Normal
Lesma Hight
Zinovy Easy
Zinovy Normal
Zinovy Hight
Serafina Easy
Serafina Normal
Serafina Hight
Selina Easy
Selina Normal
Selina Hight