Havertz, 21, is expected to leave the Bundesliga club this close season after an impressive campaign.
Chelsea are reportedly the frontrunners to land the Germany international, with Frank Lampard's side having already added Timo Werner and Hakim Ziyech ahead of next season.
Sane, who has arrived at Bayern from Manchester City, suggested a deal could already be done as he discussed two of his Germany team-mates.
"I think Germany always have very good young players, there's no question about that. I don't know why [clubs] are looking for our younger players at this moment," he said.
"I think the Bundesliga is always attractive, you can see young players getting their chances and developing very well in the Bundesliga. It doesn't matter at which club.
"Of course, in [signing] Timo Werner and Kai Havertz – two players within a single year – Chelsea did a good job. There is no question that Germany has very good youth programme.
"I think the whole world of football knows that and of course it's also appealing to other teams in the world to get such players."
Sane was long linked with a move to Bayern before the deal was confirmed earlier this month.
The 24-year-old said he wanted to win the Champions League with the Bundesliga giants, praising Hansi Flick's work at the helm.
"It is generally difficult to answer the question of who wins the UEFA Champions League. Of course, Bayern Munich has done it a few times already," Sane said.
"I was looking for something new, some fresh impetus, and for me it was clear that if I'm going to make a change, it has to be to a club that is able to win the Champions League and Bayern Munich can do this 100 per cent.
"It's a good question if we can win the Champions League in the next few years. It's not easy, but Bayern Munich is a club which definitely can win the Champions League.
"As you could see last season, the team is at the top level and I think Hansi had his impact on the team. You can see it on the pitch that everyone is having fun together with Hansi. Because of that, this was the right step and the right move for me."