List of British fencible regiments 1793-1803.
List of British fencible regiments 1793-1803: [Includes Ireland units.]
https://en.wikipedia.org/wiki/List_of_British_fencible_regiments#List_of_fencible_infantry_regiments_raised_between_1793_and_1803
Provides which units were in Ireland 1798. Very useful.