I can throttle my connection but not internet sharing?

I want to simulate different bandwidth/latency settings on different mobile devices for testing purposes. I want to set up my computer as an access point using Internet Sharing, and have the connection that goes through my computer throttled. These steps are simple enough. I can set up the internet sharing, and I can throttle the connection on my computer using Charles Proxy. The problem is that this limited connectivity I have set up does not transfer to the internet sharing, it's just bypassed. If I have a broadband connection to my computer, for example, and thottle it to simulate the EDGE network, the EDGE network is what I get when I browse on my computer, but it's not what I get on the mobile devices the computer is sharing to; they get the full broadband connection.

Is there a way around this?