You can reach the datasheet here.
You have a few things to consider.
Option 1 needs clearance behind it on the board to allow the locking tab to move.
Option 2 suffers from a higher probability the locking tab will break off due to catching on something or pulling sideways on the cable. However it does give the pins a little protection when the board is being handled. You also need to ensure there is room to unlock it when the board is assembled in wherever it is going.
If neither of those is a problem, you can chose whichever one you think looks best.
A different concern you may not have considered is, if, in the future, you decide to switch to the 90 Degree version, you will want that pointing off the board. As such you need pin 1 on the correct side, so I would use option 1.
It really doesn’t matter which way you put it. What is important is what is next to it that could block engaging the plug or reaching the release on the plug to disconnect it. Your first thought might be to place the latch to the edge of the board but if it is a tight fit into the chassis, you might not be able to get a finger in to press the release.
I worked on a design that placed a similar but larger connector at the edge of the board but when the board was placed into the chassis, it was very difficult to disconnect. My first change request for the PCB was to spin the connector 180 degrees.
Neither of your options is stronger or weaker than the other. Think, how are you going to disconnect a cable without using any violence? Be sure that you have room to do it. Designer's nose start easily to attract serviceman's fist if this is not thought.
You can quadruple that attraction by making some deadlocks: Part A cannot be taken off before part B is out of the way. Part B is not movable before A is out of the way.
Very good answers, but there is one additional factor to get your design intent into practice. If you put some clue into your silkscreen for the part to be stuffed that indicates the orientation of the locking tab, you stand a much higher chance of getting what you want here. I only say this because the attached jpg does not seem to show that. (unless it is hidden by the part, which would make it hard to verify, as I would be demonstrating here)