That's related to the MP pause feature coming in LE soon.
It would be really nice to have the pause implemented in such way which would allow both coaches to still easily navigate and observe the pitch, rotate camera, change overlays, click on any player to see its stats/skills etc. Also, some way to put a mark visible to the other coach on some square and/or player on the pitch would be of GREAT use.
When recently I got to explain BB rules to my friend while playing a match in base game (not Legendary, so no pause at all), we had really hard time.. Like, "do you see this orc around the center of the pitch? no, not that one, this one.. no, the one a bit further.. yes, right there! now try to blitz my other player over there..no, more to the left.. oh, it's right for you.. yea! Yea, and on push back, you move him to the left..no, to the right.. I mean closer to center of the pitch.. oh, my turn has ended.."
This is really frustrating experience, if you need to explain something to somebody, or point something to him, you're just totally confused regarding how to proceed. Some simple hotkey "Put a mark" highlighting a certain place or player on the pitch for a brief time, could help with such interactions immensely.
To prevent coaches from abusing this feature (like, constantly spamming marks to annoy the opposition), it should be only allowed while game is paused.
On a double thought, if it will only be allowed while game is paused anyway (so no interactions with players on the pitch is allowed), don't think it needs a separate hotkey. Would be more convenient to have it on right mouse button, for example, much more intuitive.