@wade_solarch Short answer: try to avoid that.
Back in the old XenServer days, you had to manually change the cpu feature flags so it would work at all.
https://xcp-ng.org/docs/requirements.html#pool-requirements
This confirms that you can't mix Intel & AMD in a pool
https://xcp-ng.org/docs/requirements.html#pool-requirements
This explains Heterogeneous pools a little