OUR option is free for all HSBC customers through global money. No fees at all.The bank would have to select the OUR option and this actually costs between 20-50 EUR per transfer:
OUR: The transfer fees are paid before you initiate the transfer. This means that the transfer amount is expected to be paid in full to the recipient.
https://www.expat.hsbc.com/international-banking/products/global-money/