Extract TVEPISODE & TVSEASON from FILENAME

Using the extended tags I am tagging video for PLEX. I can manage to get Titles and year from my movies because they are simply named however my TV database is extensive and randomly named. How do I get the episode and season number from the file name to the TVEPISODE & TVSEASON tag?
Filenames are formatted differently however episode and season are always formatted as follows (case varies upper and lower):

This Show S03E13 Maybe some other text.mkv (or other file type)
this show - (2019) s02e09 - Maybe some numbers and letters.mkv

Regards

Perhaps like this (with Convert>Filename-Tag):
%dummy% S%tvseason%E%tvepisode% %dummy%