Spoiler alert: EU can fine and (if needed) seize assets of companies based outside of the EU.

Only if those companies have EU assets*

Even still, if the EU chooses to regress, I can imagine a lot of non-EU-based companies—especially smaller ones—just choosing not to deal with them anymore

EU can pretty much unilaterally cut access to the financial system of said companies, demonstrated this year to a number of russian entities. Meanwhile, given what Xi has done in the last couple of years, I would not be surprised if China moves against the model makers first.