"It's a bit of a shame how it's always going back and forth," Gnabry said with the Germany team while preparing to face Italy in the Nations League this Saturday in Bologna.
"As a teammate and part of the club, I hope there will be a peaceful solution."
Lewandowski caused a stir Monday by insisting "my Bayern Munich story has come to an end" while on duty with Poland.
The 33-year-old scored 35 goals in the Bundesliga last season to help Bayern win a tenth straight German league title, but made it clear he wants to leave after eight years in Munich.
Senior club bosses have repeatedly said Lewandowski will be held to his Bayern contract, but Barcelona reportedly want to sign him on a three-year deal.
Bayern star Thomas Mueller has also waded into the debate, telling magazine Kicker that "'Lewy' has a valid contract and I would like my long-term forward partner to stay".
"Of course, the (football) business is such that things can turn out differently. In general, the club is bigger than us players," Mueller added.
Like Lewandowski, Gnabry is also out of contract next year, but the Germany winger was tight-lipped about signing an extension.
"I don't want to comment on my own contract situation here, so please don't ask me any more questions," he tersely told reporters.
According to both UK and German media outlets, Bayern are reportedly poised to sign Senegal winger Sadio Mane from Liverpool.
Gnabry, who normally plays on the right wing, declined to comment on the possibility of Mane, who plays on the left or as a striker, playing for Bayern next season.
However, Germany starlet Karim Adeyemi, who is joining Bayern's rivals Borussia Dortmund from Red Bull Salzburg, said Mane's possible transfer to Munich would be good for the Bundesliga.
"Mane is a fantastic player and I have talked to a lot of people in Salzburg about him," said the 20-year-old.
"You can see how well he has developed.
"I see him as one of the strongest wingers in the world and I think he's better there than in the centre of attack."