How to delete product properties that no longer appear in the Bitrix download?

Question

1C-Bitrix

Good time, properties used to come in the unloading, for example, the size and color of the product. Now the color property is not needed, it does not come in the unloading, but the product on the site remains unchanged. There was an option to unload the empty value of this property, but there are a lot of goods.
How to remove this property? Moreover, for boots, the color property must be removed, and for T-shirts, it is necessary. How can I delete it based on the presence in the unloading?
Maybe try to delete the entire directory and run the import? But, the catalog is big 2-3 hours import.
Thank you!