Hreflang Errors 404 vs "Page Not Found"

[rigelcable]

For a websites that differ between catalogs (PDPs) what hreflang error causes the least harm?

Obviously the best solution is to only have hreflang for shared products, but this takes more work to implement. So when no identical product exists...

1. Hreflang points to 404 or 410 error.

2. Hreflang points to 200 status "Page Not Found" page. This obviously has the additional issue of needing to point back to 100+ urls.

I want to avoid having Google decide to ignore all hreflang due to errors as many correct urls will exist.

Any thoughts?

[seoelevated]

As you wrote in your question, it is best to only link when the product exists in those other countries/languages. Both of the options about which you inquired are problematic, for different reasons. I would say that if you can't adjust the application code to only include hreflang when the pages really exist, then I think you should remove the hreflang tags from the pages, and instead manually create your sitemap with hreflang implemented there. That means your sitemap would not be perpetually up-to-date. But a slightly out-of-date sitemap with correct hreflang tagging would beat either of the options you listed above.