1. Settings for POP or IMAP access.

    POP settings

    Server name: outlook.office365.com

    Port: 995

    Encryption method: SSL

    IMAP settings

    Server name: outlook.office365.com

    Port: 993

    Encryption method: SSL

    SMTP settings

    Server name: smtp.office365.com

    Port: 587

    Encryption method: TLS or STARTTLS

You should use the PostSMTP plugin for wordpress, set up as below (substituting the correct email)