Scan to pc with different wifi modes are not working

Hi guys,

I'm looking for a solution to get the scan to pc function working with different wifi modes on my Epson XP9830. It´s working fine if my PC is connect with Wifi 4 (2.5 Ghz N), too.

The printer has no 5 Ghz only 2.5 Ghz radio but a LAN Port
On Windows or Mac there is a connector app (Epson Event Manager) which will communicate with the XP830 an provide the necessary information for the XP830

Now my PC is connected with Wifi 5 on 5 Ghz. Therefore I'm using the WRT902 in Client Mode (5 Ghz Wifi5, too) with the relay bridge and connect the XP830 in LAN Mode. Everything works now fine like it's described here:
https://epson.com/faq/SPT_C11CE78201~faq-285269?faq_cat=faq-topFaqs

Now my PC is connected with WIFI 6 5Ghz AX. This mode the WRT902 is not supporting. Therefore I cannot get the scan to pc function working. My PC is not viewable in the XP830
Epson is telling me that the function is only supported on the same network mode and they use the XMPP Protocol.
From PC side everything works fine with different wifi modes. The PC and XP are in the same network (using the relay bridge client mode).
Firewall is disabled

Does anybody know a tip and can help to get it working independent from the Wifi Mode ? (Somekind of translator mode inside OpenWRT?)

Thanks a lot

I made a picture to make it a little bit clearer.

Only if the wifi is the same. Scan to PC is working.
Vice Versa. I can initiate a scan from the PC every time.

I tried to get both Wlan (5Ghz +2 ghz). into the Relay Interface of Openwrt. But than I got duplicate IP Adresse in the 192.168.178.1/24 network.

Hmm. Hopefully somebody can point me in the right direction to get it work.

Relayd is like that. It's not really the same network.

You can do a true fully bridged link wirelessly if the AP supports WDS. This almost always means running OpenWrt on it. If you really want to keep the ISP-provided home gateway you could add another low-performance router wired to the gateway to run the WDS link to the printer. Printers and scanners don't need a huge bandwidth.