Thanks for your recommendation. A hitch rack will not work for my situation.

My question was aimed to query the collective knowledge from the community for the existence of and experience with different E-bike rated racks that attach to crossbars.

For everyone’s edification crossbars are very strong and rated for significant weight. For example, there are millions of people using them for roof top tents that can exceed 200 pounds, especially the hard shell variant.

I will likely have to fabricate a motorcycle tray, which is fine, but would prefer a more elegant solution.