How to understand signal inversion and current flow through OTA?
But aren't M10 and M7 in common source too?

and

Isn't M5 common source too?

Just because M7 (or M5) use a common source connection doesn't necessarily mean they produce an inversion - their drains and gates are connected together and this means that they don't have any inverting qualities about them at all. They are wired as MOSFET diodes: -

and: -

The quote immediately below was copied before the OP corrected the question following my observation. This has caused me to edit my answer.

M3 is said to be inverting input because: M3, M6 and M9 are in common
source configuration

No, M9 is a MOSFET connected diode as per M5 and M7.