u/Cartoonist-Motor

For me personally, I hope it would be Lost Einherjar. It maybe a great oppoturnity for them to renew it and release the 2nd volume.

Plus, since FGO isn't going to end any time soon, but it collab with many of its works already, this might be one of the best possible choice.

The artist Shirow Miwa also draw a lot of art imagine the two main servants if they are in FGO so it seems the creators themselves also want it to happen.