Is that a cockroach?

Unfortunately, the photo is unsharf – yes:
It’s a shame, but I mean a harmless forest treasure, no cockroach, no German cockroach to see!

https://www.google.de/search?sca_esv=577789025&hl=de&q=ectobius&tbm=isch&source=lnms&sa=X&ved=2ahUKEwjxzqnf052CAxXASvEDHdNjAnIQ0pQJegQIDBAB&biw=1177

For the German Sham has, like her nymphs, at the neck sign two very distinctive dark stripeswhich I cannot see in your image:

https://bugguide.net/node/view/364803

Please compare yourself, you see the animals directly on site

Again the difference:

https://bugstop.de/waldschaben-bekaempf

Forest damages are not household damages – they live in bushes and shrubs, feed on rotten plant material, so go after a few days in the house lacking food itself.

You don’t have to do anything against her.

Flying grids at the windows are enough to prevent them from entering, because they can: fly. They fly to artificial light, so they are also found in the evening or at night.

They also crawl very well and quickly, can be found at daylight and behave by far not as shy as German or other, harmful cockroaches.