Overwhelmed by multi wan + vlan setup

Hello Mirkrotik Community
I’m quite new to the mikrotik game, and have the following setup: On one side of my flat I have good 5G coverage and cable and on the other side I need internet, now I connected both sides with a single fibre connection.
I also had some fun when connecting isp1 and isp2 directly to the CCR2004 with multi wan PPC https://help.mikrotik.com/docs/display/ROS/Per+connection+classifier it is working

But I can’t get it working over the fibre with another router2 like this:
Screenshot 2023-03-31 at 18.38.19.png
I’m also not sure if it makes more sense to configure router2 as a switch or as a router, should those trunk interfaces have an ip or can I connect them via vlan?

I would really appreciate, if someone could help me to get the config right

Ernesto