I’m not quite as heavy as you 86kg (189#), but I get relatively sweaty. My long runs are 90-120min, and half marathon is my preferred distance.
I think the extra weight does increase how much you sweat, but you can’t stop it without going slower. I’d recommend a hat, to keep things out of your eyes.
I’ve never had chafing on my chest, but you could look at wearing a tighter shirt so there’s less movement. If then shirt is already tight, try looser. Maybe a singlet could be a good option for you too.
Bloody jaffas!
I joke of course. Just enjoying seeing a local on the internet