Sorry I misunderstood. I read the following statement as you wanted to send an email through Outlook with an attached file and track to see if the email had been opened.
As for using Seafile share links, yes, you can do that. I haven’t tried this, but you can go into the WebUI, choose the file, and click the share icon. Then, choose download link. You can also create it from Windows by right clicking a file and then seafile, then create download link. Then, you might try looking at the history inside Seafile to see if it shows where someone accessed it. There are other options while creating a download link, such as adding a password. You might try those things to see if it gets reported in history when someone downloads or opens it. Honestly, I don’t know right off hand.
However, as for Outlook, I don’t know that it would be even possible. Microsoft, like Apple, has been very particular with plugins and mods to their software. Unless something has changed in the last 10 or 15 years, it may require some kind of payment, approval, red tape process in order to pull it off.