I am seeing an option for using IMAP and SMTP with LoginOAUTH2 for both office 365 and Gmail but not for POP3 library. Can we use POP3 with OAuth 2.0 for office 365 and Gmail using LimiLabs?
Mail.dll's Pop3 supports OAuth. LoginOAUTH2 method is there:
https://www.limilabs.com/static/mail/documentation/html/M_Limilabs_Client_POP3_Pop3_LoginOAUTH2.htm
You may be looking at some older version, please use the most recent one: https://www.limilabs.com/mail/download
You can find OAuth 2.0 samples here:
https://www.limilabs.com/mail/samples#imap-gmail-oauth2
https://www.limilabs.com/mail/samples#imap-outlook-oauth2