Hello @kalenjiev,
Have you tried configuring Relayd instead, as suggested by @abcd ? Also, could you clarify what devices or remote nodes running Profinet you are using, and just to confirm, they are connected to the routers via Ethernet, right?
If Profinet communication still does not work after configuring Relayd L2 bridge, you might try creating a VLAN ID 0 and selecting the eth0.0 interface under the pysical LAN (br-lan) settings, as described in the topic here:
Please let us know how it goes.
Best regards,