Hi Michal,
Not sure if I got the question correctly. Do you mean – how to display EAN (or barcode) for the variations of a variable product with a shortcode? If that’s the case – you can use product_id attribute in our shortcodes, so if your variation’s ID is e.g. 123, you can get it like this:
[alg_wc_ean product_id="123"]
[alg_wc_ean_barcode product_id="123"]
[alg_wc_ean_barcode_2d product_id="123"]
Also, our barcode shortcodes have children attribute – if set to yes, it will display barcodes for all variations:
[alg_wc_ean_barcode children="yes"]
[alg_wc_ean_barcode_2d children="yes"]
P.S. Although [alg_wc_ean] shortcode doesn’t have children attribute, I can add it, if that’s what you need.
Hope this helps. And please let me know if you have any questions, or if I misunderstood the question.