So, you want the lights to work in reverse, but earlier you want them to move same.....
I don't know. Check your pan and tilt settings first. Ensure they match on both. Then deal with the second issue.
Typically, in slave mode, it is "Slave does what master does", but some intels/movers also allow for the slaves on a per slave basis(because it's set on the slave) to alter a setting.
Typically, the up/down(tilt) tends to stay the same, while pan(L/R) will be opposite. So, first ensure the lights match up first with ALL their settings. See if it works. If so, then go to the slave and reverse the pan setting and see if that gets you going in the right direction.