Rock 5B - Booting off SSD, but can EMMC also be enabled as extra storage?

I've had a Rock 5B 16GB for a few months now and have been loving experimenting with all kinds of OSes, configurations, cases, light developing, and tuning it to be a desktop replacement machine to use as a work from home PC, but also for light gaming. It is a real powerhouse that has so much potential... as long as devs continue to support the hardware.

I currently use a 980 Pro 500GB NVME SSD for boot and the OS (overkill, I know), but I also just got my hands on the official Radxa WiFi/BT unit and a Radxa 128GB eMMC module.

Booting from the SSD has been absolutely amazing. But my question is can I use the new eMMC module as extra storage for things like Timeshift backups or to store extra Steam games while booting off SSD?