Polygamy (from Late Greek πολυγαμία, polygamía, "state of marriage to many spouses") is the practice of marrying multiple spouses. When a man is married to more than one wife at a time, sociologists call this polygyny. When a woman is married to more than one husband at a time, it is called polyandry.
This narration is not authentic because some of the narrators like (Mohammad Ibn Ziyad Ibn Easa) is unknown, hence the narration is not authentic at all.
as salam alaikum
it is not difficult for all men to convince their wives to have another wife and it is not difficult for all wives to accept an husband with more than one wife. Also, it is not necessary for all men to have more than one wife and in many cases it may be detrimental for them. People differs and sometimes there are situations that call for specific choices. For example the Qur'an says: "And if you fear that you will not be able to to justice to the orphan girls, then marry of women as may be agreeable to you two or three or four, but if you fear that you will not be able to deal equitably then one" (4:3).
With prayers for your success.
Yes, unless it is a special case, like her being ahl al-kitab or if she is his wife's niece.
However, do not be allured by the promise of secrecy. Women (almost) always know!
1. It is not allowed for a Muslim man to have more than one wife if he is unable to implement practical justice between them. Allah says in Quran : ( But if you fear that you shall not be able to deal justly with them, then only one wife) ( Sura 4, Verse 3).
2. The Muslim man must keep the respect of every one of his wives and never hurt feelings of any of them.
3. The acts of threesomes is not allowed in Islam at all. Any of his wives is not allowed to see other wife during intimate situation.
Threesomes are not allowed. (Sorry!) They can live in the same house but there should be some separation particularly during intimate times.
Thank you for your question. It is not necessary for the wives to know each other or be friends in a polygamous marriage in Islam.
May you always be successful