I bought new PC on Windows 11 and I had some issues to create Yahoo account.
Automatic mode worked well but manual mode didn’t work and I needed to create Yahoo account in manual mode.
So, I found solution [Generate and manage third-party app passwords | Yahoo Help - SLN15241 (Generate and manage third-party app passwords | Yahoo Help - SLN15241)
By generate third party apps password.
it is this password that I had to use to configure Yahoo account in EMClient and now it works.