Can I play games properly online via DLAN?

Since the room can't be reached by my brother either with wireless or with cable we want to set up DLAN over the socket.
The question now is, can you play it properly and lossless online games like Fortnite?
Do I need a specific DLAN device? There's the device from 40 - 300 Euro…

If the connection fits: yes.

Buy a starter kit. TP-Link gives you one for around 30 euro. That's enough.

I use a cheap and with me it fits. Unless the connection breaks off (but less often happens). Of course, you will not get the full power of your internet connection, but if you have a good internet connection anyway, I do not see any problems there.

Definitely