What are the best options for the following situation

Current situation/workflow:

 

1. There exists a mailbox named a-mbox@bee.nl
2. One to a few (N)  information sources send messages to this mailbox. The messages in itself may, but need not, contain all relevant information. Often, not always, there will be file attachments to the messages that contain critically relevant information.
3. An employee Y in organization Bee receives the the mails which are send to  to a-mbox@bee.nl
4. Y reads the mails in a-mbox@bee.nl, followed by these actions:
   1. determines  to which of N topics the emails belongs. Y has created N folders in Outlook, one folder peer topic. Y moves the message from the inbox to the corresponding folder. The selection of the proper folder  can always be inferred from the information in the Topic line of that email
   2. decides, if any,  which colleagues must be informed about the content of an email
   3. decides, if any, action is required inside organization Bee
   4. decides, if any, follow up emails will be sent to recipients outside Bee.

Undesired consequence of this situation:

1. The decisions and actions  of Y cannot be monitored to anyone outside Y unless Y decides to send information on his actions.
2. Even if Y activates a colleague or supervisor, that person will not be able to quickly see the progress on the story/context/background and/or similar events that triggered the action.
3. Even if

Desired situtation:

1. The textual content, rather than the e-mails themselves,  of the e-mails that are send to a-mbox@bee.nl are automatically placed in a location that can be monitored by all stakeholders (being colleagues of Y) in Bee. That location must also hold a link to an attachment in case one was sent.
2. Y 
   1. (and other stakeholders) must be able to see all messages and information with a focus on one (selectable) topic
   2. must bne able to set a task for a stakeholder on an per message basis
   3. (and other stakeholders) must be able to see who was given what tasks, and when, including follow up monitoring of confirmation that task was executed.
3. All stakeholders must be able to see correspondence send by Y to external sources

Desired kind of solution: mails and attached information stored in a document library, or SharePoint list, per topic, as records, with metadata that can be used to monitor and drive all actions, manually or by using Flows and PowerApps.

 

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