One such word implying "both having an influence on each other" is correlated.
A and B are correlated .
Collins:
correlate
past participle correlated
1. [verb] If one thing correlates with another, there is a close similarity or connection between them, often because one thing causes
the other. You can also say that two things correlate.
At the highest executive levels, earnings and performance aren't
always correlated.
COBUILD Advanced English Dictionary. Copyright © HarperCollins
Publishers
ODO:
correlate
VERB [NO OBJECT]
1 Have a mutual relationship or connection, in which one thing affects or depends on another.
‘the study found that success in the educational system correlates
highly with class’