The 24-year-old midfielder will enter the final year of his contract at Mainz in the summer and has been heavily linked with a move away from the club.
Stach has several suitors in Germany, where Borussia Dortmund, Borussia Monchengladbach and Bayer Leverkusen are interested in him.
He is also being tracked by clubs in the Premier League, where Liverpool and Tottenham are believed to be keeping tabs on the midfielder.
And according to German broadcaster Sky Deutschland, Stach is open to moving on from Mainz in the summer transfer window.
The 24-year-old defensive midfielder is rated highly in Germany and has already earned two caps for the national team.
With his contract set to expire at the end of next season, Stach believes it could be the right time to leave Mainz.
The German club are also likely to listen to offers for him given his contractual situation as they do not want to lose him on a free transfer in 2024.
Mainz are ready to accept an offer of around €10m to €15m for Stach in the summer transfer window.
