Difference in noise levels between inverting and non-inverting inputs of LM386
Signal to noise ratio at the output of an amplifier circuit depends on:

The noise figure of the chip (stated in the datasheet at a given bias point)

External network (designer needs) which fixes the gain

Temperature


To answer your question:
One can't say that that the inverting input is less noisy.
It depends on the bias point of the chip and on the voltage gain.