If it is an MUS team, from what I read, they will probably want to give you Cognitive Behaviour Therapy.
If you're lucky (relatively speaking) this will be to help you with coping strategies for chronic illnesses, if you are unlucky, it will be the sort of distorted CBT used by some psychiatrists, including in the infamous PACE trial, in which they will try to persuade you that your symptoms are the result of false illness beliefs - ie that they have no physical cause (which is bullshit).
If you are even more unlucky they will want to put you on a graded exercise therapy program in which they will try to persuade you to increase your activity levels each week and push through the symptoms you get as a result of doing too much. This can be severely detrimental to the health of anyone with ME which includes post exertional malaise.
These services are run by psychologists, nurses or occupational therapists, and do not involve doing any further medical investigations, though when you first go you may be assessed by a doctor.
It's worth finding out exactly what they are offering before committing yourself to the 'treatment'. You do not have to go along with anything you are offered if you think it will not be helpful to you.