The issue with 2 way speakers placed horizontally is the vertical dispersion. Generally speaking speakers have wide, but not tall seating areas. The vertical dispersion tends to be from the tweeter and below, and response gets noticeably worse above the tweeter axis. In other words, you usually want to sit at twitter axis or below.
This can vary a lot, and is minimized by high-order filters. If you have 4th order crossovers it doesn’t matter but often 2-way speakers have 2nd and 3rd order filters (often 2 on the LP and 3rd order on the HP). So, to answer your question, you want the tweeter to point to the outside of your listening area and your midwoofer inside.