What Coleman stove are you trying to connect? Depending on what Coleman stove, you may find a YouTube on how to fabricate, or where to buy a third party adapter. The Coleman's typically depend on a regulator at the stove to reduce the high pressure LP. On your trailer, the regulator is at the LP tanks. You can't have both regulators in sequence, or not enough gas will get to the stove.
There are several threads on this throughout the forums, and if you dig deep enough, and use a little ingenuity, you should be able to get it to work, as many of us have done.
Be Safe, and Everyone Goes a Home,
2014 RAM Laramie 2500 w/6.7L Cummins Diesel and Automated Safety Hitch
2016 377RLBH Jayco North Point
300W of Suntech Solar w/Rogue MPPT Controller & Xantrex 2000W PSW Inverter