@PilarRubio since it's only for a few products you would need some custom coding to be done. I'm sending a collaborator request to assist on that should that be ok. Let me know!
Don't forget to Mark As Solution & Like to make the answer more visible to the community, Cheers!
Hi @Geraldine123 !
How can we help? Would you mind sharing your store's URL so we can provide the solution?