Collaboration between different Proton Users to manage joint inbox

Hi all! I am looking for an efficient way to manage one “central” email address with different Proton users but I am getting confused on the different plans, namely the Mail Professional and Proton Business plans. I am trying to set up something like the below and would love some suggestions for which plan would be most suitable for this scenario (if it is at all possible to do) or what other Protonmail features I could use to set up something similar to this.

I am looking to put in place a system where there would ideally be one "central" email address (e.g. [email protected]) that customers can reach out to. Additionally, there would be a number of individual accounts (with their own email address, password, etc.) that would all have access to that central mailbox. I.e. if someone reaches out to the [email protected] address, all individual accounts would also see that email in their inbox and the individual would have the option of responding to the customer email either with their own individual address or the central one in the "From" line. Ideally, all individual users would also somehow be able to see, whether a customer email to the "central" address had already been responded to by one of the individuals who would have access to that inbox. So, basically, I am looking for a way to manage incoming emails to a joint inbox with multiple users, without having to share a password.

Any suggestions on how I can use Mail Professional or Proton Business plan features, or something like auto-forwarding to achieve something similar would be appreciated 😊