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.