Compatibilty: "ESXi 6.7 U2" or "ESXi 6.7"
This shouldn't matter to the guest OS, it concerns only the downward compatibility of the VM (if you vMotion to an ESXi host with an older version).
Guest OS Family: "Linux" or "Other"
Guest OS Version: "FreeBSD 12 or later version (64-bit)" or "Other (64
bit)"
I use "Other" and "Other (64 bit)", but it doesn't really matter. ESXi chooses some defaults (number of CPUs, size of RAM) and suggests e.g. the emulation for the SCSI controller. You can change any of this later, if you feel like it. NetBSD supports for some versions now the VMXNET3 driver, which is really great.
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