As Prairie Chicken mentioned, the seats will physically swap over no issue. His reference to sedans should only apply to the rear seats as you indicated both were Jetta's. Two door Golf & New Beetle (front) seats will have the fold/tilt forward function and could still be used in a 4 door (Gold, Jetta Sedan/Wagon). I'm currently using a New Beetle passenger front seat in my Jetta wagon.
As for the harness connectors question ...
Did either the car you're putting them into, or the car they're coming out of have heated seats? It's a separate connector and I'm not aware of any connector changes over the years.
I can't recall what year(s) the airbag connector changed, but as he mentions you can just re-pin the donor seat over to your plug.
Lastly swapping any wire integrated into the seat belt buckles is pretty straight forward.
Worse case, I'd say is you might lose heat (if you car had heat and donor seats don't) & you might end up with an airbag light until you can re-pin the plug (if needed).
I'm south of Atlanta, if you need any help.