If you have installed the app in /home/senaite then folder for report templates is:
/home/senaite/buildout-cache/eggs/senaite.impress-xxx.egg/senaite/impress/templates/reports
Replace xxx in the path with version you have installed.
If you are using Senaite Health, then the path should be:
/home/senaite/buildout-cache/eggs/senaite.health-xxx.egg/bika/health/impress/reports
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