Let’s put it put it this way: a majority of foreign companies would be considered as foreign corporations under US Law except the check-the-box rules, that’s a major exception. You can choose what the company will be irrespective of its default classification under US Tax Law.
So, in your example if the US Company, a limited liability partnership would create a SARL outside of the United States and transfer the assets, (I’m going to use this example a little bit later again, because it’s going to be very interesting as with respect to pointing out a specific reporting requirements), so in this case, if they were to transfer all the assets to that SARL company, and they would file a form 8832 choosing for this company to be treated as a partnership, no problem. The IRS will accept its designation as a partnership as long as it’s properly named, timely and properly.
If this were SA as I’ve mentioned a societe limitee, then check-the-box rules would not apply. Per Se corporations are always corporations; Check-the-Box rule exception does not apply.