I use the iVANKY 8-in-1 Docking Station, works great with my ROG Ally X.

You can search on Amazon to find some best selling ROG Ally X docking stations. There are plenty of good ones.

I bought JSAUX docking station for ROG ALLY X. Works well.

UGREEN Dock 9-in-1 USB C Docking Station is OK. https://www.amazon.com/UGREEN-Docking-Foldable-Ethernet-Compatible/dp/B0CR6JND4M?tag=7649-20

Jsaux 6-in-1 Multifunctional Docking Station
This dock is specifically designed for the ROG Ally X’s thicker chassis and side-mounted USB-C ports. It includes a 7-inch USB-C cable to reach the ports comfortably and supports 4K@120Hz via HDMI 2.1, Gigabit Ethernet, and 100W PD charging. At $45.99, it’s affordable and guarantees compatibility, unlike many older docks that struggle with the Ally X’s design changes. Plus, it works with Steam Deck and Lenovo Legion Go, making it versatile if you own multiple handhelds.