If you want to dress fashionably, wear flat front pants. But if you want to dress
well, wear pleats!
But most importantly, wear what you like!
I couldn't find it in an acceptable length of time, but a few years ago I reposted a blog article by a young man who had received his first pair of well-tailored pleated trousers. They may have been bespoke. And he was slender young man. To paraphrase, he said, "I'm surprised, these make me look trimmer!"
Well tailored, properly cut and properly sized pleats do
not make you look fatter. It's the opposite. Given all of that, both forward and reverse pleats can look good, but I think forward pleats look better. The difficulty is in all the qualifiers; poorly tailored and cut, improperly sized pants of any sort will not look good, nor will you in them. And that's the problem, most pants do not meet one or more of these qualifiers.
So, wear what you like, you probably won't look any worse than the guy standing next to you. (Unless, of course, he happens to be Vox. But then, I doubt that he'd really be willing to stand next to you.

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