AppleScript to create a new Outlook email using selected text as subject?
See if this works for you:

set varSubject to "Hello"
set varContent to "GoodBye"
set varName to "Jon Snow"
set varEmail to "jsnow@castleblack.org"
tell application "Microsoft Outlook"
    set newMail to make new outgoing message with properties {subject:varSubject, plain text content:varContent}
    make new recipient at newMail with properties {email address:{name:varName, address:varEmail}}
end tell