I haven’t got all my research to hand but regarding Bavarian flags….
Bavarian Infantry flagpole, length 2.04 m (without lion topper)
Bavarian Infantry flag, per square side 1.17 m
One of my own 28mm (Eagles of Empire) flag bearers (for which I used the bigger than scale EoE flags):
For more detailed info, I refer you to screen grabs of the TMPer Napstein:
Hope this helps