I purchased all of the classes from the wildemount sourcebook, and I dont see the content in the character builder.  (i.e. there is no echo knight under fighter)

Make sure that the Critical Role Content is toggled on (red, to the right) on the Home tab of the character builder.

I'm having the same issue and the toggle does nothing. I also notice that I now have the option to purchase EGtW in the store even though I already own it.

Please see the content accessibility FAQ sections A & C for helpful info: (https://www.dndbeyond.com/forums/d-d-beyond-general/bugs-support/142100-how-to-access-content-on-d-d-beyond-faq). If that doesn’t sort you out then post back here again.