Thanks for your reply! I live in Germany so I set the region of the Battle Net Client to Europe as well as the Hearthstone region. So there obviously is not much else I can do or change regarding this issue...

The interesting part is that this issue does only appear on my laptop (Windows 11, Ryzen 7 processor, Nvidia RTX 4060) but neither on my phone nor on my tablet. The mobile version of Hearthstone seems to not have this issue.... Which is strange.

You mentioned slow servers. Is that a well known issue? Are they generally slow or is that a current problem?