Well I am going to try and make this as simple as possible.See the definition of work is :
Work is defined as the product of a Force and displacement of the point of application of force in the direction of displacement.
As you can see in the bolded section Work done on a body has no relation to the displacement of its centre of mass.It merely depends on the displacement of the point where the force is acting.In case of pure rolling the point where friction acts lies at rest with respect to the ground.So displacement of this point is zero.Since friction acts only at this point the work done by friction depends only on the displacement of this point not on the displacement of centre of mass.So since displacement of this point is zero Work done by friction is also zero.
Now for the swing example: Here the normal force merely serves to cancel out gravity.When we stand up of the ground there is always a net force acting on your centre of mass that displaces it by h and causes a difference in potential energy of mgh.
Change in Mechanical energy = Work done by you
So net work done equals net change in mechanical energy =mgh. But when you are on a swing there is an additional downward force acting at you centre of mass which is the centrifugal force.When you raise your centre off mass by h height this force does a negative work since it acts opposite to the direction of displacement of your centre of mass so you have to do more work to create same potential energy difference.
Change in Mechanical energy = Work done by you + Work done by centrifugal force.
If work done by centrifugal force = -x Then,
Change in Mechanical energy = Work done by you + (-x)
or, Change in Mechanical energy + x = Work done by you
So naturally you have to do more work to stand up on a swing than on the ground.
Basically the difference between these two cases is that Friction acts on the bottommost point in case of pure rolling which is at rest so friction does zero work.
But The centrifugal force on the swing acts at your centre of mass so since you raise your centre of mass by height h the centrifugal force ends up doing negative work so you must do some extra work to overcome that negative work done by centrifugal force.
Please let me know if you have understood or do I need to elaborate ?