Yes, you should probably file two separate Schedule Cs. One advantage of doing so would be that in the event that one of the LLCs has 3 years or more of losses and the other shows profits, you’ll be able to show intent to make a profit for at least one of them. That way both your LLCs wouldn’t be subject to the Section 183 hobby loss provision. I don’t really see any benefits (other than convenience) of combining them anyway.