Will I be able to speak to interpreters only in InterStar ICP?

Yes. InterStar ICP allows you to speak completely independently from the main event. For example, you can mute your microphone in the main event but your microphone in InterStar ICP can be unmuted and you can talk to you boothmates separately.

By the same token, when you’re interpreting your boothmates will be able to talk to you in case of emergency, but that audio will not be heard in the main event because InterStar ICP is a completely different audio system.

You can even handover quickly by muting your main event microphone and asking your boothmates in InterStar ICP to take over.