I have seen this heavily debated in the past.
The general consesus is usually, that it depends on the DM.
As for line of sight rules about "Wall of force", you might want to take a look at this answer from another post:
Basically for the sake of for example spells, the wall gives total cover anyway, which means it would make people behind it untargettable, thus sort of breaking line of sight (akin to the age old debate over glass windows)
Something you'll have to think about is the following:
For the duration, you see invisible creatures and objects as if they were visible, and you can see into the Ethereal Plane.
Ethereal creatures and objects appear ghostly and translucent.
This means, you'll see the wall as it would appear if it weren't invisible.
The question is, what does the wall look like? The name suggest it is compromised of pure 'force', whatever that may be. One might even be inclined to think of it as etheral, which would make it seem translucent.
If I were to rule this exact situation, the wall would appear translucent, but would block line of sight effects, since that is a big part of the Spells use after all. But again, take it with a grain of salt.