Using EN200U-CN in USA with China roaming SIM

Technical Subjects
1

HI, we have developed one of the project around EC200U-CN, Can our Sales team show the demo functions to USA based client using roaming activated China Sim / any other Asian country Sim.

Will this work / we needs to assemble and send the hardware module EC200U-EU ?

2

I would say that neither of these models are suitable for the US.
You just need to take the list of bands supported by the modem and compare it with what the operators of the region of interest use.