How to type any unicode symbol in outlook?

Simply type Unicode Hex Value for the character & press Alt + x.

Eg: Type 905 (Unicode Hex Value for Hindi letter अ), select this number & press Alt + x .

You can find list of all unicode characters here & also get their Octal, Decimal, Hex & HTML value.

Reference: https://www.quora.com/How-is-the-approximate-sign-made-on-Microsoft-Word