I was reading the Monster Manual and got to the beholder (Monster Manual, p. 28). It says that the beholder can target three targets it can see.
Yes, but there are some concerns.
Unlike fog cloud, the wall can be circumvented since a wall illusion wouldn't spread the whole 20ft cube like the fog cloud spell. Even so, if it interacts or pass the investigation check, it will be able to see through the illusion. Last but not least, while major image can make a decent wall, minor illusion is just too small for that with its 5 feet cube size. The beholder can choose several squares to be looking at you from as a large creature with eyes all around it (with perception +12 nonetheless). Also, same weakness of the previous spell.
But for sure you can force it to get close to you with those spells, even if you get 4 casters to pile up 4 minor illusion spells to hide behind it.