I was extremely cautious at first with foods that are often mentioned in relation to blockages, but over the couple of years since my ileostomy operation, I've been gradually adding more and more in, and I now eat sweet corn as well as other things like nuts (very regularly! I often eat them multiple times a week), mushrooms, popcorn, coconut, salad, things with skins and seeds, etc., and have had zero problems. I try to make sure I chew carefully, of course, but apart from that, I don't really worry about blockages anymore as I haven't even had an inkling of one! The first few times I ate sweet corn, I chopped it up a bit so there were no whole kernels, but I haven't bothered to do that in a while; I just chew well.
I think everyone is different, though, so you have to judge it on a case-by-case basis and take it slowly if you do try anything. It seems like adhesions are a common problem that can increase the risk of blockages, but I assume I must not have any, or at least not to a degree that causes any issues. I'm guessing also that the size and flexibility of the stoma hole will vary from one person to the next; presumably, mine must be on the larger side. I've had occasional slightly larger lumps of undigested stuff (maybe a bit bigger than half a corn kernel size) in my bag, so clearly, things can get through OK! Obviously, I can't say whether this will also be true for you, but you can only really know if you try. As I said, start slow with small amounts and chew well; if that goes well, try a bit more, but don't get too laid back about chewing as it's not worth the risk even if you're one of the luckier ones like me who isn't prone to blockages; you can never say never.