Question about ASUS ROG Swift PG348Q

It depends on what functions it has to have. An inexpensive solution if you want a simple mount would be the Vogels Base 05M.
(Vogels Base 05M (Wall))

Just make sure that the mount supports VESA 100 x 100mm and that the weight of the monitor is not too high, which is unlikely to be the case.

I myself opted for a table mount. Have fun with the beautiful monitor.