I had the same problem and resolved it this way:
My host provides phpMyAdmin which I used to Export the database file Inventory, in CSV. Then I edited the downloaded file to use replace etc. then Upload with Replace ticked.
However, I had a problem. I changed the product NAME also, and now my HTML files still have the same old name and so does the SEO. I need to update these but I haven't been able to find where the old name is stored. That was why I was looking here. So be careful what you change. Don't change column 1; the id.