The WooCommerce Discontinued Products plugin does everything you need to make your products inactive, without mixing them up with other stock statuses:
The product can no longer be purchased.
The Discontinued text (which you can set on the plugin settings page) appears wherever your theme would normally display the In Stock/Out of Stock text.
If you have enabled the image label option on the settings page, then a text label will also appear on the product image. This appears on your main shop pages as well as the product page.
Depending on your plugin settings, the products may or may not be hidden from the rest of your shop.
Search engines can still access the discontinued product pages, so you won’t lose the SEO value of these pages. (If you want to remove them from search results, then check out our advice on how to do this.)
The product will not be included in your reports of other stock statuses such as ‘Out of stock’, so it won’t mess up your stock reports.
You can view and filter by discontinued products separately in the WordPress admin.