Your biggest issue is the Generator Outlet requires a MALE Plug and your 'Trailer' power plug requires a MALE Plug
The adapter posted above will plug into your Generator 30A outlet BUT your power cord would need 2 male ends....1 to plug into adapter and 1 to plug into 'trailer' receptacle
That is called a SUICIDE cord....male plugs on each end so when plugged in exposed prongs are HOT....electric execution
That is why you can not/will not find an adapter to plug the gen and trailer together
Need to change receptacle on trailer AND on female end of power cord to twist lock types
Swap receptacle on 'trailer' with CEP/Marinco 6375M Male Plug 50-Amp 125-Volt/250-Volt Twist Lock Inlet Connecton
Swap female end on power cord with Marinco CS6364N 50 Amp, 125 Volt//250 Volt, Connector
You will still need that adapter to plug into generator and plug your male end of power cord into adapter
