Actually I've been trying out a bunch of files and 125Mbps is the highest bitrate I can play on quest2 over wifi.
Viewing post in Slow speeds inside of Heresphere on Quest 2
I don't have any videos above 125Mbps to test, so I can't say for certain whether the app can play those files smoothly. Is the device you're using to provide the video files connected directly to your router with an ethernet cable? Maybe that'll help improve the speeds. You can also try lowering the playback speed (there's an input box in the bottom of the seekbar) to see if that helps reduce the freezing.