Woocommerce: Bulk edit prices of variable products

Hi
My client’s WordPress/Woocommerce website sells 200+ photographic prints at various sizes. If he wants to increase the price of all the variations of all his products, is there a way to do this without individually editing each product? Am I correct in my understand that global changes to the prices of variable products cannot be made using the basic WooCommerce plugin? Bulk editing the product pages only enables me to set a single price for all products/variables. The client is not proficient enough to download/upload the products as a spreadsheet for editing purposes so ideally I’m looking for a plugin or Woocommerce add-on. The client’s previous website (using Photium) enabled him to set global groups which, when applied to products, enabled him to make bulk price changes to all products to which a particular global group had been applied and edited. Does anything similar exist for Woocommerce? Any help and advice would be gratefully received.
Regards
Paul

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