For obvious reasons can't post this at UKTS where it might reach a slightly wider knowlege base, but I seem to be struggling to find a decent freeware UK style AC catenary set for MSTS. There's some Woodhead gantries and an Australian style system but not much else.
A quick search of the forum seems to indicate at one time Rob Thorburn aka "Goingnorth" uploaded a set of Mk3 catenary but this got pulled when he, as sadly have so many of us over the years, ran into trouble then came the falling out and suspension/resignation/ban resulting in the toys going with him.
Perhaps someone who knows the file library better than me could say if anything is available. Failing that I have the Swedish ones I can copy over from my Inlandsbanan route which are not ideal, but about the best I can manage. Suppose I could see if there's anything kicking about on the French or German sites too.
And yes, as you can gather despite various challenges I'm having yet another attempt at reviving the old dinosaur. There's still a few little corners of the UK which haven't been included in one of the "mega routes" and more than enough of the wider world left to do.