When you choose a report, i.e. Constituent Summary you have the Column "Primary Address?" That can not be translated because is it not in any po-file. There is "Primary Address". In CRM/Report/Form.php : ts('Primary Address?')
UPDATE: This should be available for translating in transifex now as per the recent announcement in the chat translation channel. This was updated today: https://lab.civicrm.org/dev/translation/blob/bb10330a29b701e898dd41ff062e6dd53075f512/po/pot/report.pot#L2162
It looks like that was only fixed in the code about 5 months ago (see here) so may not have moved into transifex yet. I'm not sure what the schedule is.
Probably the best place to ask language questions is at https://chat.civicrm.org in the Translation channel.