I would find the use of 'polis' odd. Usually a word in the contemporary language is employed because the concept is important and translation would run the risk of distorting the meaning. The downside to that is it increases the mental load for the reader.

In the study of ancient Greece the scholarly community used to use 'city-state' which was effectively a translation but was immediately understandable. A broad consensus developed that this was misleading and that it would be better to use 'polis' and explain what that meant (harder for the reader, but important enough to be worth that effort_.

Using the term polis to describe something from outside of the society that used that word offers the worst of both. It is effectively a translation, just like city-state, so could be very misleading, and it also has all of the mental load for the reader.

So probably avoid it unless it is being employed specifically in relation to an argument that Rome in its early history was organised in very similar fashion to a contemporary Greek polis, but even that argument might be better made without the label.