From which software are you printing the e-mails?
On the off chance that it is Apple Mail, I sent an e-mail to myself from a different e-mail account of mine with a BCC to that different account. When printing the e-mail as the original recipient or the BCC copy, neither printout showed the BCC's.
On a Mac since 1984.
Currently: 24" M1 iMac, M2 Pro Mac mini with 27" BenQ monitor, M2 Macbook Air, MacOS 14.x; iPhones, iPods (yes, still) and iPads.
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