BCC to dynamic mail address (in kombination with CF7)

Hello,
I use Contact Form 7 and an option to send a mail as a copy also to the prospect.
Unfortunately, in combination with Post SMTP no additional recipient addresses are taken into account about it, can it be?
Does anyone know how to *dynamically* add another recipient address (“BCC”) in Post SMTP – preferably in combination with Contact Form 7?

Thanks for any tip
Jürgen