  Collisionless simulations of structure formation with significant local
primordial non-Gaussianities at Mpc scales have shown that a non-Gaussian tail
favouring underdensities, with a negative $f_{\rm NL}$ parameter, can
significantly change the merging history of galaxy-sized dark matter halos,
which then typically assemble later than in vanilla $\Lambda$CDM. Moreover,
such a small-scale negative $f_{\rm NL}$ could have interesting consequences
for the cosmological $S_8$ tension. Here, we complement our previous work on
collisionless simulations with new hydrodynamical simulations of galaxy
formation in boxes of 30 Mpc/$h$, using the {\sc RAMSES} code. In particular,
we show that all feedback prescriptions being otherwise identical, simulations
with a negative $f_{\rm NL} \sim -1000$ on small scales, hence forming galaxies
a bit later than in vanilla $\Lambda$CDM, allow to form simulated galaxies with
more disky kinematics than in the vanilla case. Therefore, such small-scale
primordial non-Gaussianities could potentially help alleviate, simultaneously,
tensions in cosmology and galaxy formation. These hydrodynamical simulations on
small scales will need to be complemented with larger box simulations with
scale-dependent non-Gaussianities, to statistically confirm these trends and
explore their observational consequences in further detail.
