Perhaps a silly question, but have you ever had allergy testing to confirm a bonafide allergy to zinc oxide? The only reason I'm asking is that it may not be the zinc you are reacting to, but perhaps one or more of the other ingredients or fragrances found in the ointments you've tried. Also, if you do have a true zinc allergy, zinc is naturally found in many foods and is a common ingredient in many over the counter products and medications (oral, topical or otherwise) so you may want to investigate further so you are not putting yourself at risk.
If you are looking for something that does not contain zinc, many people swear by straight up Vaseline (also sold as white petroleum jelly). Although Calmoseptine is still my go to barrier cream, I have used Vaseline when I was unable to obtain Calmoseptine, and I can vouch for the fact that it works and is soothing. Cons are that it is greasy and may stain clothing if you're not careful in how you apply it, but the obvious pros are that it does work, is available almost everywhere and is very inexpensive.
Hope you find something that works for you.