Most likely a rumor yes. I don't think Manchester United is an option for Ronaldo since he wouldn't return to a club that doesn't play in the Champions League. The guy is so ambitious that if for some reason he would miraculously return to Europe, he would only do it if he can prove that at the age of 40 he can still score goals in the most important football competition on the club level in the world. He wouldn't want to play for a sinking ship like Manchester United, whether there is some history that binds him to the club or not. He would rather go to a top 10 club and be the first striker in the team and then try to get that team as far as possible in the Champions League competition. But no, he is earning too much money and that will keep him either in the SPL or end his career altogether. But since he wants to keep playing for the national team, I think we will see him play in the SPL until at least 2026.
Sporting CP would be a good choice if the superstar's ambitious goal is to return to the Champions League.
A move to Sporting CP would put Ronaldo in a position to return to his first club and show, at 40 years old, that he can still perform at the highest level of football. It would be the perfect situation for any player with such enormous ambitions. He would then keep himself onside with the Portuguese national team too, an outcome that surely outweighs anything else as far as priorities go leading up to the 2026 World Cup.
Furthermore, it would have to be weighed financially and also take into account his wishes and the club's strategy. Though it may sound far-fetched for Ronaldo to depart the SPL with all the perks he has earned, returning to Sporting CP to stamp an elegant endpoint to his career is not beyond the bounds of possibility.
For me, Ronaldo should have finished and if Ronaldo still wants to continue his football career with the big ambition he has, I think it will be in vain and may make the view of Ronaldo bad. Because after all, only playing in the Saudi Pro League and playing in the Asian Champions League, in reality Ronaldo finds it difficult to score many goals like he did playing at Real Madrid with the many goals he has scored every season.
Thus, if for example Ronaldo returns to play in Europe, then of course Ronaldo will have great difficulty in scoring many goals. Thus, I personally am not sure there are any top European teams playing in the Champions League and are willing to bring in Ronaldo. Because with his big ambition to become a striker with the most goals, it could be highly egotistical and also, his expensive price will make top European teams think twice about bringing him in.