Only the RX had power folding mirrors, the normal EK9's have power adjustable mirrors and the Race Base had manuals.
I'm afraid I don't have a clue about differences between 4s and 9s but I don't think there are any as I bought some APR carbon mirrors and they are listed as fitting all 96-00 Civics and considering the Canadians never got the EK9 (APR is Canadian) they bolted straight onto my 9
Also, if i was to replace mine with some non power folding mirrors (as mine are scuffed up and someone wants to buy them) would i need anything else apart from the switch from the donor mirrors car?
the pre facelift had power folding mirrors too, i changed mine for non power folding mirrors as they were lighter. the power folding ones were slightly bigger too, i cant tell you about the ek4 mirrors sorry.
Mine had Power Folding mmirrors but unfortunately they got smashed up so I got another set of an EK9 which were not Power Folding and it fitted in fine...plugs are the same, just the button which folds the mirrors don't work anymore.