It's been the position of the ADA for the past 10+ years that humans are not obligate carnivores.
The micronutrients that vegans need to watch out for are EPA/DHA (types of omega 3s) and Vitamin B12. Both are trivial to supplement, and not particulary expensive (especially now that Costco sells the former). The B12 you get via factory farmed meat is all supplemented to them anyway, so there's no difference in some hypothetical molecule quality.
The last remaining micronutrient that might be tricky is Vitamin D3, if you don't get the necessary sun exposure. The D3 in standard supplements is usually made from sheep wool. But you can also replace that with relative ease, and many vegan options are really mixed D3+K2 supplements which is even better. Also available at Costco, for what it's worth.
The core of any sin is against the will i.e. I have heard there were people who would like to be eaten and found a guy who actually ate him.
In the book I AM THAT Sri Nisargadatta said to a questioner:”
Look, my thumb touches my forefinger. Both touch and are touched. When my attention; is on the thumb, the thumb is the feeler and the forefinger -- the self. Shift the focus of attention and the relationship is reversed. I find that somehow, by shifting the focus of attention, I become the very thing I look at and experience the kind of consciousness it has; I become the inner witness of the thing. I call this capacity of entering other focal points of consciousness -- love; you may give it any name you like. Love says: 'I am everything'. Wisdom says: 'I am nothing' Between the two my life flows. Since at any point of time and space I can be both the subject and the object of experience, I express it by saying that I am both, and neither, and beyond both.