Mercury in Aquarius is how you think and talk mental, social, articulate.
Aquarius Mercury is at home — quick, plural, articulate. The mind connects across distance. Conversation is the medium where the thinking actually happens; you do not know what you think until you say it. Your fixed tends to hold — to stay with, to commit, to outlast, which colours how this Mercury actually shows up day to day.
The shadow: overthinking, gossip, sharp speech weaponized against tenderness. The work is befriending your specific kind of mind instead of fighting it.
Practice: notice the speed your mind likes. Do not borrow another sign's tempo. Read what your tempo reads best. Speak to who actually listens at your speed.