I'm running Resurrection Remix (Android 7.1.1) on my new Mi5s Plus and installed the latest stable FreeDcam (3.3.147) from https://github.com/troop/FreeDcam/releases/tag/3.3.147. I presume this version isn't meant for Nougat, as video recording fails.
I installed 4.1_alpha22 from https://github.com/troop/FreeDcam/releases/tag/4.1_alpha22 and while it allowed me to change the setting for 1080P to 60FPS under camera1, VideoLAN player reports that the recordings are only 30FPS. Also, in 4.1_alpha22 (unlike 3.3.147), there's no option to enable EIS.