Not really given it much thought TBH but something will happen very soon !Under what scenarios though, and who has the right to the appeal? I would hope an appeal could only be "granted" during a break in play, and perhaps only the captain can make the appeal to the referee. For scenarios, offside/not offside when a goal has been scored (and either side can challenge); penalty/no penalty when the referee has blown for the spot kick (defensive side can challenge) - what else...?
who would the be video refs?
Not necessarily. Is there any need for the refs to only do one game? Most weeks there are only 10 or so games going on at the same time and, if use of the video ref is limited, two or three refs with feeds from all the grounds could probably handle it. Also, it would be an ideal role for top level refs who can no longer handle the speed and fitness required so would not need to eat in to existing high level ref numbers.If this was applied in the EPL only then you are looking at 10-20 extra officials per weekend.