Sane has been linked with a move to the Bundesliga champions after the departures of experienced wingers Arjen Robben and Franck Ribery at the end of last season.
Bayern chairman Karl-Heinz Rummenigge revealed he is hopeful a deal could still go through, with Sane expected to make a decision over his future once he returns from his off-season break.
"He can definitely help us. Period. Exclamation mark. He has showed that in the national team and at City," Kovac said.
With attacking replacements high on the agenda as Kovac looks to build on last season's domestic double, Barcelona's Ousmane Dembele another player on Bayern's radar.
"He is a very good player, too," Kovac said. "We are focusing on the attacking area because we lost two players [Robben and Ribery] that we need to replace.
"In the 'six position', we have [Joshua] Kimmich who can play there and Thiago [Alcantara] who did a great job. We have got options. I know that there will be more to come.
"The ambitions for this season are very high. We want to defend our double and perform much better in Europe. We want to improve what was good and what was bad."
Speaking at the presentation of new signing Jann-Fiete Arp, Kovac conceded it is not easy seeing off competition from LaLiga and Premier League sides for the world's top players.
"It's no longer club against club," he said. "We have to fight against states, against billionaires.
"There is more money available for a club like Bayern, but it has become much more difficult for Bundesliga clubs.
"[Borussia] Dortmund have brought in players from the Bundesliga, not from outside, like the best players play in Spain and England."
Arp joins defenders Lucas Hernandez and Benjamin Pavard in making the switch to Bayern and is expected to provide back-up to Robert Lewandowski.
"There is no better player than Lewandowski to learn from as a young striker," Arp said. "Everything is going well so far, it's fun being here. I've got to know my team-mates and the coaching staff. I want to train and develop at this level."