I can eat large onion when it is sliced very thin, and very little quantity, for example in a salad. Otherwise, I prefer smaller raw scallions, spring onion (even the white part), shallot. As for red onion, my tolerance is very slightly better than the big white or yellow onion. A few days ago, MIL made a salad full of onions, I just picked out most the onions and discreetly discarded them. My month and throat started to sore and feel scratchy and discomfort.
I don’t usually eat leek raw, but there is a Peking duck recipe that I made occasionally, with the rich sauce, slice of duck, the raw leek is delicious and isn’t offensive at all.
No problem with all of them cooked.