VPN to Dynamic IP (with DDNS)

[WhiteTiger]

I would like to realize this scenario:

• FW1 with OPNsense and WAN with static IP.
• FW2 with software not under my control; it can be OPNsense or something else or even a simple router.
• Both have Wireguard.
• FW2 WAN is with Dynamic IP and a DDNS.
• FW1 must create a VPN to FW2 (not vice versa, from FW2 to FW1).

Is it possible to achieve it?
What precautions should I take into consideration?