My home airport is MAN.
MAN T2 is a single long terminal with the gates laid out on one side.
When you exit the aircraft, you will be in a sterile corridor that runs along these gates, one floor below the departures level.
This corridor has the immigration hall in its centre.
But directly opposite immigration is a small corridor for transit pax.
I have never done it, but once I had a 4-hour layover in MAN because it was cheaper to fly MAN-AMS-MAN-EWR-MCO than MAN-EWR-MCO and more miles of course!
Since I didn't feel like hanging out at the Air France lounge (pretty decent BTW) for 4 hours, I decided to go through immigration again.
But not before asking the gentleman guarding the corridor if I could go through for my flight to EWR.
He said no problem, just go through the Transit corridor and it takes you back up to departures level.
I believe there is a security screening but it's highly unlikely there will be any queue, I've never seen one there.
So, in short, you'll probably even have time to get a drink and some pastries in the Salon Air France!