You asked

Should I upgrade from the olympus pen e pl8?

Here is what the site says about that.

From Olympus PEN E-PL8: Olympus PEN E-PL8: A mirrorless camera by Olympus with a 16.1-megapixel Micro Four Thirds sensor, announced in 2016. Specs - Maker: Olympus - Mount: Micro Four Thirds - Sensor: Micro Four Thirds, 17.3 x 13mm, crop factor 2.0 - Resolution: 16.1 megapixels - Stabilisation: in the body - Announced: 2016 - Type: mirrorless camera Focal lengths on it Lenses frame like 2.0 times their focal length on full frame: 12mm like 24mm, 18mm ...

From Buying used: Buying used: Cameras and lenses are built to last, and many photographers upgrade often. That makes the used market one of the best ways to afford good gear. A body that's one or two generations old is often most of the camera for a fraction of the price.

Quoted from this site's pages.

From these pages