how do I import woocommerce custom fields into my wp site?

I am using several plug ins like yoast seo. I have downloaded my products from the site and have added several. when I go to import the new ones i see all the yoast seo and other listed as custom fields and none of these are uploading with the spreadsheet. I have 900 new products to add and to go thru all of them to fix this would be daunting. Any ideas for me? thanks you in advance