Composite readings

Composite Mercury and Venus

A composite chart is built from the midpoints between two people's charts, so it is one chart for the pair rather than a chart for either person. These readings say what a placement in it stands for in a pair's shared chart.

Together

Composite Mercury conjunct with Venus
The pair's thinking and its affection meet, so talk and enjoyment tend to share the same ground, with conversation, humour and common interests close at hand.
Composite Mercury in an easy aspect with Venus
How the pair talks and what it enjoys go along well, so exchanges tend to feel agreeable and shared interests surface without effort.
Composite Mercury in a hard aspect with Venus
How the pair thinks and talks and what it finds pleasing differ in taste, so what interests it and what charms it only partly overlap.

None of this is a verdict. A single placement never describes a whole relationship, and astrology is a tradition of interpretation rather than a body of established fact.