It’ll probably be much, much easier to just pull a backup fr your Flint v1 then cherry pick fr the tarball (via 7zip) the confs to upload to your Flint v2. See the attached HOW-TO; there’s a caveat when it comes to custom firewall rules.
This all assumes the Flint v2 is still running iptables & not nfttables as the mainline OWRT 23.05 is now based on (opkg list-installed | grep iptables).
I would use the Flint v1 to port scan the Flint v2 via nmap (opkg update; opkg install nmap).