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The HPE MicroServer Gen10 is NOT officially supported on ESXi.
As you can see from the matrix, the only MicroServer that was supported was the Gen8 machine.
So although you _can_ install ESXi on this machine (I've installed HPE Custom image ESXi 6.7U2 without any problems during install), some of the features might not work and won't be supported.
One example is passthrough. If you check the available PCI devices in the Hardware tab ... you'll notice that none of the devices in the machine are supported for passthrough.