Tested on VyOS 1.4-rolling-202201100317, on also on previous 1.4-2022 versions
Its not possible to add rules that contains "matches everything except" pattern.
Neither of this works (they where all tested separately, in fresh install):
set firewall name FOO rule 10 protocol !gre set firewall name FOO rule 10 source address !198.51.100.1 set firewall name FOO rule 10 source port !22