So you'll have to try each method and see what works best.
Very very few phones support USB to Ethernet so if your's does, that could be the fastest way but you must test this setup.
Again, anyone that tells you this or that is faster will be guessing. Just set it up and test.
So basically, I'm hosting a lan party and looking at alternatives to my sky q router as we get slow internet speeds.
I want to use my phone in usb tether mode and connect it to my switch with a OTG cable and cat5. Will this work and share that connection to anything plugged into the switch? How will this affect connection speeds?
The other option is to just tether it to my PC and share the connection through windows network sharing center.