Will 2019 27" Imac MRR12LL/A run Mojave 10.14.5, Bootcamp Assistant and allow installing of Windows 10

Bought this unit 1 week ago, tried to create Bootcamp partition to install Windows 10. Drive hung up and stalled during partitioning process. Got replacement unit from Apple store, (they said drive was defective), updated Mojave to 10.15 and updated Bootcamp Assistant, will this model run Windows 10? Should I use Mojave 10.16? I'm familar with Apple discontinuing support of 3T fusion drives, but what problems with 2T fusion drives, Mojave, and Bootcamp Assistant? Can I install High Sierra instead? or is that even possible? High Sierra doesn't seem to have the problems with Fusion drives.