So as far as Cristiano Ronaldo is concerned, at the moment we are on three rumors
-Saudi Arabia for 220 million euros over 3 years.
-Arsenal because of the interview that became famous
-Chelsea has recurring rumors about this sign but nothing concrete at the moment
I see Arsenal as the least possibility. Because they aren't in need of a striker at the moment. They definitely don't need to spend a lot of money only for Ronaldo in January. Even though Jesus hasn't been scoring goals for two months Arsenal have still been doing very good in their league games. The team effort is already at a high level so they don't need to splurge on a player now. Arteta has a quite nice budget in his hands now which is the truth but he would use it more effectively like increasing the number of good player alternatives.
Saudi Arabia might be like last resort for him in case he doesn't find a team in Europe.
For Arsenal, so far Arteta is only interested in young players who have talent. I even doubt if the Arsenal Management are interested in Ronaldo for them to sign in January, even though Ronaldo is currently a free transfer. there are many things that will be considered by big clubs, to bring in Ronaldo in January. apart from the huge salary, he will also ask to play as a regular player and because of that, until now Chelsea has not issued a statement.
I'm pretty sure Arteta will buy a few players in January, but not Ronaldo. only Chelsea, who have always wanted him so far however, there has been no agreement between Ronaldo and Chelsea.
on the other hand, a very high offer came from an Arab club. however, Ronaldo said he was not interested. So, let's wait after this world cup is over.