Yes, that's ok. I'm usig now a 1K/1K2 voltage divider
with a zener parallel to the 1K2 resistor. In that way
3V3 signals are 'level shifted' to 1V8 signal levels.

A zener is really needed to fight ESD, did tests with
an ESD gun for many many hours years back. Just hoping
that the on-chip PN-juntions will help you withstand ESD
is begging for trouble. Adding a simple zener and you
can withstand 16kV full contact charge injections, almost
without end. You can forget about the 'two shot 4kV human
body model air discharge' and all that when a zener is present.

intron