Can't change Server. It's broken

[sephiroth-24437]

It’s intentional. There are no regions to select. You get put in the games that have the best connection. So basically connected to the server that’s best for/closest to your location.

More info here:

Crossplay update soft region locked everyone

Hey everyone! Today’s Global Battle.net update has caused some confusion in the community about region locking and swapping, so let’s take a moment to provide some clarity about details that might not be immediately clear: Why can’t I swap regions anymore? The simple answer is, you are placed into the best match based on a variety of factors including player skill and ping. Getting more technical, it’s because the regions themselves no longer exist (at least not in the way players tradition…