If it's not too inconvenient, I would like to request the full VOD be uploaded as the raw files, in a different collection just for the raw stuff, then make the items with separated matches.
That said, if you have prohibitive internet caps or something, it's ok if those raws come later.
For the cutting, I wouldn't recommend that tool.
Essentially, my recommendation depends on how much time you're willing to spend encoding, and most importantly, why you're re-encoding at all.
But really, based on some tests I just did, h264 (.mp4) looks much better than vp8 (.webm) for the same bitrate and encoded about twice as fast (hardware has been made to work well with h264 for a long time).
The newer versions like vp9 and h265 and AV1 would have like 30% or 50% better bitrate for the same perceptive quality, but the encoding time is far longer right now; about 6 times as long in my test, so instead of spending 30 seconds for 2 passes on a 30 second clip, you're spending 3-5 minutes. So unless you have patience or know about hardware acceleration, I would just download Handbrake (a graphical front-end to ffmpeg, that IIRC mpv uses anyway) and use .mp4 h264, same framerate as input (constant), set the Constant Quality to something that looks good (test it on like 10 seconds of action), 2 pass encoding, and the Preset slider to the slowest you can tolerate (probably 'slow' or 'slower').
Use the Range bit up the top to make the Seconds you want to start and end on, I have mpv side-by-side and just copy in the timestamp of when I want to start and end.