Which email widget can combine and display inboxes from various email accounts?

[AC Question]

I'm used to near-stock ROMs and have always used the stock AOSP email app from Google. It works perfect and you can use 1 widget to combine and display the inboxes of all my (five) email accounts.

I've recently turned to a different phone and OS (cannot flash custom ROM), with it's own email app. This app doesn't allow you to make a widget to display multiple inboxes, it can only show the inbox of one email account at a time.

I've searched the Google Play Store, but I am yet to find an email app/widget that allows me to combine all inboxes of all my email accounts into one widget.

If you have any suggestions, I'd be happy to hear them