I don't think there's anyway to make yourself poop without being able to hold it unless you have surgery of the bowels and I wouldn't recommend that.
You don't need to become bowel incontinent to poop in diapers when you want too.
I poop in diapers all the time and even pee in them without being incontinent. I gave up the toilet a few years ago and wear diapers 24/7 and still am not incontinent either bowel incontinent or urinary incontinent.
Although my bladder has gotten a bit weaker and I can't hold it as long as I used too but that's not a problem since I wear diapers and pee and poop whenever I need to.
So if you want to poop in diapers just poop in them and to make yourself poop more often try eating more fiber and prunes or prune juice or take some laxatives to help you poop more.