Why is it so hard to get outlook.com installed on any email client? I'd get a new email address in GMail if I didnt' have to change the email at so many services.
Have you enabled 2-factor authentication on your outlook account? I had a similar problem some weeks ago and the solution was to enable 2-factor auth on my account.
Are the email clients you have tried installed as .apt or .deb (not snap or flatpak)?
I know Outlook email is supported by Thunderbird, as that is what I use on multiple platforms. There was an issue a few months back when MS introduced oAuth security. See this, and links within that refer to Outlook.com Get started with Thunderbird | Thunderbird Help
Thunderbird, Betterbird & Evolution all should work with outlook.com.
And noted by jesseekoh, you will have to use 2 factor authentication. If I recall correctly when setting up outlook.com the setup process directed me to go to my Microsoft/outlook account and "authorize" it to work. Hope this helps.
I just use outlook from the tab i made in bookmarks in firefox
When adding MS mail accounts depending on the client you may get a prompt to grant app permission in the form a MS login dialog. I see this in the cross platform mail client that I use. Make sure the dialog input box isn't hidden under an open app window. I've not seen this , but it's possible.