Use tabbed chat, (it's in the settings on the comms panel), then never enter the player chat tab. You will still get the NPC comms, but player comms will only be visible if you intentionally tab over to it.
It's in the game already. *sort of. All player chat that you would see in solo would be in "system" chat.
It's possible to place "system" chat to hidden.
Settings in com panel. 3 options hidden, tabbed, main.