Thanks for the great feedback.
1- It’s not a plugin setting & I doubt it’s a plugin issue, it might be how you’re allowing quantity input in archive pages (or theme, for example OceanWP changes “add to cart” to “view cart”), I’ve tested it using plugin “Quantity Field on Shop Page for WooCommerce” and it worked, added same product twice from archive page.
2. Yes, and that should be default if you enable quantity on archive, that’s why I think it’s somehow related to the way you added quantity there.
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