Thus my plot is the following: I would cover display with transparent film, using the fibre-tip pen with permanent ink map to this film the relevant Compact SeedQR and then, after placing this film on the steel plate hammer it with a punch tool.
I am unsure how efficient that idea would be considering the method. My main fear is that somehow your copied QR code isn't recognized and you are left with a metal plate that is not useful to your needs. I would tell you to test it before copying it to the metal plate but that would make you to use an exterior device (which I believe you don't want to).
Sure, I will test more than once both transparent film mapped with Compact SeedQR and its copy on the metal plate until get the satisfactory results. Besides this plate will serve as the second-class backup for SEED. The stainless-steel washers with the stamped seed-words are nights and days in my garage.