Hi Danny,
Since product variants on the same detail page probably won't work for you, I think this is going to come down to how creative you can get. There are plenty of phone case manufacturers out there that all have different descriptions of their products which are essentially the same thing. Try to approach it from that angle, treat them as though they are different and start with a clean slate for every product.
You might want to have different people in your organization tackle similar products, so they're written from a different voice. When the same person writes all the descriptions, they end up using the same adjectives and thinking about the content in the same way, so it's hard to break the pattern on the 2nd, 3rd, etc. product descriptions.
