According to the changelog, the latest beta update brings some new features, including the slow-motion feature for the front camera, Auto Hotspot feature, and more. You have already seen these features in the first beta. It also adds the November 2019 security patch.
The software version of this update is G970FXXU3ZSJF, G973FXXU3ZSJF, and G975FXXU3ZSJF for the Galaxy S10e, S10, and S10+ respectively. The size of this update is around approx. 450-500MB.
If you want to check for the update manually, you can do this by heading into the Settings > Software update > Download and install.