I have "hEX S" router connected to RB260GSP switch via SFP
and then my PC is connected to ether1 (PoE) on thet switch
and other PoE devices are connected to ether2,3,4,5.

I have created/establish L2TP-Client/OPVN-Client session to the Server from the "hEX S" router,
but would like to get all the traffic from my PC ether1 on the RB260GSP to
go via that the L2TP-Client/OPVN-Client session on the "hEX S" router.

Is it possible? If so, how?
Or does the PC have to be connected directly to "hEX S" router?

Is it possible to create more L2TP-Client/OPVN-Client session and assign them to the other specific etherX ports on the switch/router?

To dhcp leases of your mikrotik make your PC MAC bind to IP and your computer will get same IP every time! Then use mangle to mark traffic from src-ip (your computer IP) and route it through VPN

Looking at Mangle Rules in IPv4 Firewall, the Chain has 5 options:
- forward
- input
- output
- postrouting
- prerouting

The wiki about Mangle
https://wiki.mikrotik.com/wiki/Manual:IP/Firewall/Mangle
does not explain what exactly it is that I want.

Would you be able to help with CLI comand pls?
My local IP that I want to route via the L2TP connection is 192.168.168.68
The L2TP connection is called l2tp-out-UK-vpn

Thanx in advance.