You may not want the foreign person to own an interest in a US LLC. If the LLC is engaged in a U.S. trade or business (e.g., through your activities in the U.S.), the foreign owner will be deemed to be engaged in a U.S. trade or business. Creating a foreign entity of which you own 50% may be better. There are some complications/filing obligations to creating a foreign entity, but your partner can avoid U.S. tax.