When displaying multiple products that are basically the same, let's call them Product A with different sizes, 30, 40 and 50, I choose to create only one page per product and avoid duplicates, since the size would really be the only difference.So in this page, I'm displaying the different product codes based on their size, ie: A30, A40 and A50.On a different page, for example, where Product B is listed, I would like to display related products, in this case, Product A (only a list with sizes and codes, no pictures). I can either display Product A by itself (which I don't want to, since a Product B30 would fit a product A30, for example), or display Product A30, A40 and A50.Using schema.org, itemprop=url, I would like to link to this product's page.The question here is, product A30, A40 and A50 are all listed in the same URL. Would linking these 3 products to the same URL pose a problem?
Schema.org product variations with same url. Problem?
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If Product A is an accessory or spare part for Product B, this shouldn't be a problem since you're using the isAccessoryOrSparePartFor property, which is:A pointer to another product (or multiple products) for which this  product is an accessory or spare part.It's natural to list accessories on the same page as the corresponding product, and provide a link to another page for more details on them. And as previously covered here, several products can be listed on a single page.This is akin to having a page for a printer (Product B), and then listing various printer cartridges (Product A) there as accessories, which point to a cartridges page that contains content like pictures of the cartridges, compatibility, specs, etc... It's doubtful that a search engine would view this as a form of manipulation or otherwise since you're indicating the accessory/product relationship, and this type of structuring is common.