After having another look at eglot-x.el i don't
think eglot--apply-text-edits (plural) is the right
place to put the generic.  You'd just repeat a lot
of code of the original, with no clear way to reuse it.

Maybe you want something more akin to the attached patch,
which introduces eglot-apply-text-edit (singular).  In your
override for this function you can check conditions to either
proceed with the non-standard edit or delegate to the default
implementation with (cl-call-next-method).

João