My recommendation for Mac power-user email client is MailMate. No question. No contest.
However sometimes work security policies force you into Microsoft-Exchange-land and your only choice is to use Outlook for Mac
You won't ever be able to make Outlook work as well as MailMate, but you can do a few things to help you get closer. MailMate Smart Mailboxes can be somewhat mimicked using Outlook Smart Folder feature along with the Raw Query option.
Outlook mail search is based on the Mac Spotlight search and index system. So make sure you
have Spotlight enabled for mail in
System Preferences → Spotlight → Mail & Messages:
⌘⌥F to enter
Advanced Search mode, then click the
Item Contains drop-down and select
Now you can enter your raw query in the text box. The raw query is Spotlight query syntax and fields.
To find out what fields Spotlight makes available, run
mdls on an Outlook mail message file.
In my case Outlook stores mail messages under
~/Library/Group Containers/UBF8T346G9.Office/Outlook/Outlook 15 Profiles/Main Profile/Data/Messages/*/*
$ mdls 8459FCED-2F8B-6A2E-B12E-1BC7C3DFFE33.olk15Message com_microsoft_outlook_accountID = 3 com_microsoft_outlook_completed = 0 com_microsoft_outlook_flagged = 0 com_microsoft_outlook_folderID = 166 com_microsoft_outlook_forwarded = 0 com_microsoft_outlook_has_attachments = 0 com_microsoft_outlook_has_mentioned_me = 0 com_microsoft_outlook_has_reminder = 0 com_microsoft_outlook_has_text_content = 1 com_microsoft_outlook_hasDueDate = 0 com_microsoft_outlook_hasStartDate = 0 com_microsoft_outlook_junkLikelihood = -100 com_microsoft_outlook_messageReceived = 2019-08-04 19:18:22 +0000 com_microsoft_outlook_messageSent = 2019-08-04 19:18:19 +0000 com_microsoft_outlook_primaryCategory = 0 com_microsoft_outlook_priority = 0 kMDItemDisplayName = "AWS CodeBuild www-site Complete" ...
Use those fields to form your raw query. For example I have a Smart Folder named
where I want to include anything in the
Later folder folder or that is flagged
and that isn't completed yet and isn't in the
(com_microsoft_outlook_folderID == 123 || com_microsoft_outlook_folderID == 154 || com_microsoft_outlook_flagged == 1) && com_microsoft_outlook_completed == 0 && com_microsoft_outlook_folderID != 166 && com_microsoft_outlook_folderID != 162
You may also find the below Apple Script helpful. Select a folder in the Outlook UI and run the script using Script Editor, it will log the folder id of the currently selected folder.
tell application "Microsoft Outlook" get selected folder end tell