Are Anomers Epimers?
IUPAC basic terminology of stereochemistry defines anomers and epimers:

Anomers
Diastereomers of glycosides, hemiacetals or related cyclic forms of sugars, or related molecules differing
in configuration only at C-1 of an aldose, C-2 of a 2-ketose, etc.
Epimers
Diastereomers that have opposite configuration at only one of the two or more stereogenic centers present in the respective molecular entities.

So yes, anomers are a subset of epimers.
(Interestingly, on the contrary, ‘anomer’ term is exceptionally used in much broader meaning than ‘epimer’, in the term ‘anomeric effect’, which became generalized to e.g. conformations of molecules completely unrelated to saccharides.)