It's always pink for both players. It happened 2 days ago when I was spectating a casual. It's happened again today while watching a ranked. Both times the barrier was placed on top of an existing barrier. I have not seen spectated any other games in that time where both players have played Illusory Barrier. So it's a 100% hit rate so far. The casual happened to be the Walking Carpets tournament finals which was recorded. In the recording it's clearly blue. So the bug only was visible when I was a live spectator. I am using the Steam version of OSX, if that makes any difference.
