I don’t know about Sweden but bringing in scabs is generally illegal in Germany. That is, you can’t bring in temporaries, you can, of course, hire more people but then you’ll have to keep them, and of course they can strike.
Amazon was quite successful keeping unions out here because the kind of people they employ aren’t terribly union-affine, also, noone wants to stay at amazon anyway, but Tesla? A car manufacturer up against IG Metall? In East Germany? Tesla can either cave, leave, or get beaten into submission.