Any territory curses or any other effects are mentioned in the Major Effects section of the Interlude page.
Highguard being truely hardcore doesn’t need curses to cause deleterious effects to their territories, we have synod judgements we pass ourselves :).
As mentionen the list of Great Works is the place to find this stuff out, for anything that has already been built. But I believe there are a number of Great Works currently being built, to find them you’d need to search the wiki for Senate Motions mentioning Great Works and a territory name. The other method is to look through all the Senate Motions for each season here - https://www.profounddecisions.co.uk/empire-wiki/Recent_history.
As the senator for Bastion I know we’ve got a bunch of great works being built, but off the top of my head I don’t know how many would affect people with congregations.
One other thing to keep in mind is that some Great Works benefit is split between everyone who has resource X in a territory and you won’t be able to work that out without legwork on the field .
To be honest if you’re looking for a place to stick your chapter, I’d look for a territory with less chapters, or less large chapters.
Off the top of my head, Reikos I think had the most chapters/players in it? But that’s gone through a lot of changes recently so I honestly have no idea which territories are the most populated by players atm.