Have just recognized that there is an inconsistency in the calculation of bounce rates: For entry pages, the bounces are divided by unique page views, whereas for exit pages, the bounces are divided by overall (not unique) page views.
This is confusing as for both statistics, only unique page views are displayed in the respective plugin and thus, I was not able to reproduce the bounce rates for exit pages.
Would be great if you could change the basis for the calculation of bounce rates (with regards to exit pages)! 
Thanks for the report, I created a ticket at Exit rate should use visits to the page, not hits · Issue #2069 · matomo-org/matomo · GitHub