My understanding of their use was to allow subvocal communications if you don't have headware that can communicate thoughts. IE: If you need Essence 6, it lets you still be part of the team chat.

Commlinks: Even the most basic of them includes AR Matrix browsing capability, multiple telephone and
radio modes of real-time talk and text, music players, micro trid-projectors, touchscreen displays, built in high-resolution digital video and still image cameras, image/text and RFID tag scanners, built-in GPS guidance systems, chip players, credstick readers, retractable earbuds, voice-access dialing, textto-speech and speech-to-text technologies, and a shock and water resistant case.
Micro-transciever: It doesn’t do anything special, it just lets you communicate by voice with other micro-transceivers and
commlinks that you (and the other person) choose, within a kilometer.
Wireless on the micro-transciever just extends range, RAW.