Baseboards for cork flooring - where and which ones?

Disadvantage of gluing: If the cable routing is done behind the strip later, it will be difficult to remove it without damaging it, correct?

You don't necessarily have to damage the strip, but removing the glue behind it is of course more laborious than unclipping it. Ultimately, it depends on how often you do it.

How did you do the corners? Miter cut or fitted with special corner pieces?

Personally, I don't like corner pieces, no matter which.
In other words, miter cut.

Do you have any experience or advice regarding the bonding of baseboards to the vapor barrier?

The vapor barrier was installed with an overlap of 5 cm on the side (according to the instructions).

For bonding the baseboards, I definitely have to cut them at floor level, otherwise the baseboards won’t hold, correct?

The vapor barrier was installed with an overlap of 5 cm on the side (according to the instructions). For bonding the baseboards, I definitely have to cut them at floor level, otherwise the baseboards won’t hold, correct?

Yes, of course. Cut them at the floor surface edge and the problem is solved ;)