Update:
If I specify SHORT_ADDRESS directly in the template, it is possible to create a VM using another BUS, however, as the FUNCTION is explicit, I can only create a single VM with the same template
onetemplate show 3 -x
<PCI>
<BUS><![CDATA[45]]></BUS>
<DOMAIN><![CDATA[0000]]></DOMAIN>
<PROFILE><![CDATA[nvidia-720]]></PROFILE>
<SHORT_ADDRESS><![CDATA[45:00.4]]></SHORT_ADDRESS>
</PCI>
onevm show 30 -j
"PCI": {
"ADDRESS": "0000:45:00:4",
"BUS": "45",
"DOMAIN": "0000",
"FUNCTION": "4",
"NUMA_NODE": "0",
"PCI_ID": "0",
"PROFILE": "nvidia-720",
"SHORT_ADDRESS": "45:00.4",
"SLOT": "00",
"UUID": "aa874448-6a29-5f4a-8838-58d6373c2e57",
"VM_ADDRESS": "01:01.0",
"VM_BUS": "0x01",
"VM_DOMAIN": "0x0000",
"VM_FUNCTION": "0",
"VM_SLOT": "0x01"
},