Auto label OR message tip if email sender is external

[siri123135]

Hi

Is it possible to add a header with message TIP or auto label (sensitivity label) email if its sent from external? 

I want to label all emails sent from external users automatically.

[#2]

@siri123135 
You can use Native external sender callouts on email in Outlook

[#3]

Hi @siri123135,

have a look at TagExternal for Exchange 2013/2016/2019