Allied aircraft set to "invisible" will also disappear from data links.

[Admiral_ZIPANGU]

I set my KC-135s to "Invisible" so that they would not be attacked by enemy aircraft, but they would be invisible not only to enemy eyes but also to friendly Link 16s. Of course, there is an AWACS in that airspace, and the other aircraft show up in the datalink, but not that tanker.
To test this, I removed the "invisible" setting and the tanker shows up in the datalink.

If I set an AWACS like the E-3A or E-2D to "invisible", it will still show up in the datalink, but the KC-135 will not. This is too much of an inconvenience.

[Grimes]

You can't specify which units are invisible to others. The option is on/off and applies to all AI. However invisible units can still broadcast their own datalink to a network. 

Tanker set to invisible: AI AWACS can't "see" the tanker, thus it isn't on datalink. *

AWACS set to invisible, has EPLRS (datalink) task: AWACs broadcasting its position to datalink network. 

AWACS set to invisible, EPLRS (datalink) task disabled: AWACS not visible on datalink. *

* Being the caveat that player controlled aircraft should still share their datalink radar contacts. So in the example of the tanker if a player had their radar on and detected it then other players on the datalink network should see it as long as the player sharing it still detects it.