The territory of future super-region is going to comprise the current regions of Alsace, Champagne-Ardenne and Lorraine.
I don't think it's one of my best works, but it's still worthy to share a proposal I designed:
The four quarters are taken from flags with a diagonal stripe, so I decided to arrange them forming a saltire. They are, respectively: Haut-Rhin, Bas-Rhin (mirrored), Champagne-Ardennes (mirrored) and Lorraine. Haut-Rhin and Bas-Rhin are the two provinces of Alsace, notice how the regional flag is a mix of both.
The result can be a little odd, but not less funny.
Comments and suggestions are welcome.
I'll try something more elaborate next week.