system
Given the following post, respond as if you're commenting on Reddit:
human
[MCU] what would happen is I ran through a sling ring portal from the back?

Would I be able to pass through? If I ran through from the back and someone ran through the front at the same time would we collide?
gpt
It works both ways. Front of portal A connects with the back of portal B, front of portal B connects with the back of portal A. 

If two people ran at the same portal from opposite sides, they'd miss and just appear on both sides of the second portal.