Spells like Mass Suggestion require that the target(s) must be able to hear and understand you.
The Great Old One’s Awakened Mind allows a Warlock to telepathically speak and be understood by anyone that understands at least one language (not necessarely those the Warlock knows).
My question is : within the Awakened Mind’s 30ft radius, can you affect creatures with Mass Suggestion even if their known languages don’t include yours ?