Many issues DRS has to clear up for it to have any chance of being adapted in a suitable way for football.
I think it's possible, but it'll serve up major contradictions,
no review for a free kick award which could result in a goal
no review or continuation of play allowed for an attacking team when an incorrect offside call is made (play must be stopped) - yet a goal conceded can be reviewed
Those are big problems, because the solutions to them (i.e. allowing play to continue after the offside call is made/having reviews for a free kick award) would involve changing the dynamics of the sport itself. Given that's not a viable or desirable option, we would have to accept some glaringly unfair aspects of a review system.
Overall it can't be a perfect system and won't be completely fair in all manners. But it would still cut out a lot of the decisively wrong decisions that get made now.
Given the fast-paced nature of the game, the only times a review could realistically take place without ridiculously disrupting the flow of the game imo is to challenge a "goal given", "goal disallowed" and possibly a penalty decision. No other decisions being available for a video referee make any practical sense (including free kicks near the box). There's always a large enough delay between a goal scored and a restart, or between when a penalty's been given and taken - which is crucial for a system to fit into the game as seamlessly as possible.
But once the governing bodies get past what can be reviewed, they have to determine a bunch of other stuff too. For example what to look for and how far back they should be allowed to go in their replays to identify any situation (e.g. offside, out of play, foul in the build up etc) where a goal can be disallowed or penalty not given. Number of reviews available (imo every goal and penalty should be reviewed) have to be determined too.
A workable system can be achieved, but no matter how it's implemented it's probably going to be complex and there will be a lot to clarify with a lot of hot talking points.