Hello Kostas,
is it possible to only import new products to VirtueMart?
Virtuemart product import in CSVI is based on product_sku field. If the value in product_sku field from your import file is not found in virtuemart products table in database CSVI inserts a new product, if product_sku value is found the product is then updated. So you can try importing new product_sku values for new products.
Kind regards,
Tharuna
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