Don't see much chance of Joe starting in midfield today - but like the idea of it in general, looking at how players might do in other positions. People might not agree with who could play where, but why rule out trying a *quality* player in another position.
Like, right now we have 4 really good CBs fit. Not trying to bash Kostas, but with Robbo out, could Gomez [who was a FB] do a better job there. Suppose could depend on whether you want to defend more than attack.
You like Joe for the middle, I'd be curious to see how would do Joel there, carries the ball well, quick enough, tall.
I'm not a fan of Ox in the middle for most games anymore, but think he could be effective in the front 3 - would be worse there than Origi/Shaq?
We've seen Fab can play at CB. Milner at FB.
Don't think it's as off the wall as some might think.
I don't mind trying players in different positions, but Gomez isn't a midfielder.
DM is a challenging position to play in Klopp's system due to all the positioning and pressing actions among other things, hence it took Fabinho 3-4 months to get up to speed when he joined the club.
Having Fabinho move from DM to CB is much easier than the reverse, due to the tactical complexity of the role.
As for Marip, I think he did play a couple of games at DM for Schalke back in the day, but again I doubt we'll see an out-and-out CB playing midfield anytime soon. Klopp has tended to push more attacking players back in the lineup, as in, he's far more likely to put an attacking midfielder like Wijnaldum at DM than he is pushing a CB forward. Ox and Elliott are other examples of Klopp pushing attacking talent 'back' in the lineup to get more skill and goals into the team.
Regarding Ox, the issue with him in the front 3 is that his goal output is rather mediocre, certainly when compared to the 'fab 4' up front, which is why Klopp wants him at CM rather than in one of the three attacking positions where goals are expected regularly.