https://xenbits.xen.org/xsa/advisory-412.html
https://xenbits.xen.org/xsa/advisory-414.html
The XSA-412 patch applies cleanly to Xen 4.16.2, the XSA-414 hunks four lines offset.
The other 12 XSAs (326, 409-411, 413, 415-421) since 4.16.2 (2022-08-18) seem to be of DoS character and of varying relevance.