@Iwren
There don't seem to be any classes or even standard approaches for "learning to live as HFA".
I have a personal view of it though:
IMO NT's
and young Aspies don't, and cannot, easily understand the nature or scale of the communication gap between NT's and ND's.
Yet "every" ASD masks, and masking is about mitigating the effects of the communications/interaction gap.
Aspies are no more inclined to listen to advice about this kind of thing than NT's are, so i doubt you can use this, but ...
... for me, they key to learning to get along in an NT dominated world was to start actively working on understanding the gap, and developing techniques to consciously bridge it. It's a big job - think of it as a "continuous improvement process" rather than a solution - but it worked reasonably for me.
Note that is not the same as commonly used techniques like "mirroring", which (AFAIK) are picked up unconsciously, and relatively young. An adult can do better if they're prepared to "grasp the nettle".
I sometimes wish the medical profession would stop playing around and look at doing something helpful for us.
Like a (voluntary) class for young adult and adult ASDs on "how to act normal".