If someone enters the mosque during the khutbah, can he greet with salam?

Yunus narrates that when Hasan would enter the mosque during the sermon, he would offer greetings of peace, and the people would respond to his greeting.

Ibrahim states that the predecessors used to reply to greetings during the Friday sermon and would also say "Yarhamukallah" to someone who sneezed.

Hazrat Hakam and Hazrat Hammad, regarding the person who enters the mosque on Friday after the arrival of the Imam, state that he will offer greetings (salaam) and the people will respond to his greeting. When he sneezes, they will say "Yarhamukallah" to him.

Hazrat Aamir and Hazrat Salim say that on the day of Friday, the greeting of Salaam will be answered and the Salaam will be made to be heard.