In our shop, we maintain many email addresses on more than one domain name: 'hello at example dot com', 'support at example dot com', 'admin at example dot com', 'hello at example dot net', 'support at example dot net', etc.
We are a tiny shop (~2 people), so the mailboxes should be shared. Ideally, when a customer emails us at 'support at example dot com', we should be able to reply as 'support at example dot com' (i.e. not our personal email like 'john at example dot org').
What email services do you recommend for managing large amounts of email inboxes?
I have evaluated Google GSuite, Amazon WorkMail, and Microsoft Exchange Online. Google GSuite (see: Use a group as a Collaborative Inbox) is unsuitable because it would reply to customer's email using my personal email address (e.g. 'john at example dot com') instead of the group's email address (e.g. 'support at example dot com') by default. The "Collaborative Inbox" cannot be accessed using IMAP. Amazon WorkMail is mostly featureless. That leaves Microsoft Exchange Online, which supports free "Shared Mailboxes".
What email services do you use for your company?