Credits
Translation taken from here
Initial translation and editing: Neyla ~ Kiiroi Senkou
Initial quality check and proofreading: DimensionSlip

There are a few characters I haven't identified yet, mainly in the left and back groups (and I don't know whether it's worth trying to tag each one). However, I was able to determine which group corresponds to which scenario, which should narrow it down. They are:

• Right: Star Fragments
• Front: Echoes of Paradise
• Left: The Crystal Land and the Guiding Light
• Back: Savior of Light and Darkness

The protagonists for each scenario are listed on Aselia wiki here.