Now this works (in 1.12) pretty good EXCEPT for the fact that if there's a Beacon in the area - The invisible player starts showing particles from the Beacon effects.
Beacons also causes problems if I try adding an effect like 'Regen' to the poition:-
If they use the potion outside a beacon's range - no particles show
If they then enter a Beacons range - they start showing Particles
If they next LEAVE the range of the Beacon - they will STILL show particle effects for the effect given by the Beacon - e.g. the Regen effect mentioned earlier
I was/am hoping there's a commandblock method that'll test for invisible players, whether they are showing any particle effect' & if so remove them from other players view - however the Admin won't allow any scoreboard function so that'll could cause problems
This was from three years ago so I'm not sure why I just spent the time to make an account and respond, but if you're still looking to do this I don't necessarily have a method to make that work, but I do have a workaround. I believe you can use a command block to do essentially what the beacon is doing, though you'd lose the laser (I think there might be a way to get it back into the game though without an actual beacon, or you could just have a dud beacon that does nothing if you want the laser that bad). Anyway, when you use the command block to basically do-
"/execute at @a[distance=..<HOWEVER FAR YOU WANT>] effect give at @a <WHATEVER EFFECT YOU WANT> <DURATION> <AMPLIFIER> false"
-it will generate a beacon-like effect range without any particles to worry about. The cool thing with this feature is that now with the same space it took you to make a beacon that only gave 2 effects of very limited variety, you can create about a dozen or so repeating command blocks, all with their own or multiple effects, of MUCH greater variety (since you can exponentially increase the duration and amplifier, as well as choose from a greater selection of effects.) I used this same method without a set distance to essentially create a leveling system, where better effort earns stronger effects, thus simulating the concept of growing in strength. The only downside was that I had to force load the command blocks so they would work everywhere a person went, but for a beacon-like effect it should be more than enough to just leave it be.
I know you can also do this on Bedrock edition, though I don't know the command for that off the top of my head.