Localised sites such as pt.SO, ja.SO and ru.SO have been hidden from the Hot Network Questions list.
However, questions from rus.SE do appear, as has just occurred:
Can rus.SE also be excluded from the Hot Network Questions list?
One of these days we'll make a checklist for all the different things we have to tweak when launching (or importing) a non-English site.
... but today is not that day.
Fixed, but it will take a bit for the hot questions cache to update and drop questions from rus.SE.