“I’ve got this great full-time job offer in Germany, but they want to hire me as a freelancer.”
This isn’t always ill-intentioned, but when your company offers to hire you in Germany as a full-timer but wants you to write them invoices as a freelancer instead of employing you, they might not have your best interests at heart. Or they might just have no clue about how employment law in Germany works. In any case, it might cause some serious problems for them and for you later down the track.