spoke size for bafang FM G320.250.R hub with different sized flanges

[Pharmhand]

I bought this hub for $30 in a 26 inch rim thinking that I could mount it in 700c rim. As I get ready to calculate the spoke size I realize that flanges are 2 different diameters The on- line spoke calculaterss only allow for flanges that are the same size. Any thoughts on how I can figure out the spoke size?

Bafang FM G320.250.R 26" 250W DC36V Front Wheel Electric Motor Rim JUMP Bike

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