BBC Sport understands that the Anfield club's level of interest in England international Guehi this summer is linked to Palace's asking price for the defender.
Last year, Palace rejected four offers from Newcastle with the final one reaching £65m.
However, Guehi has just 12 months left on his deal meaning he can leave for nothing next summer.
If a deal for Guehi can not be reached during this transfer window, Liverpool would be interested in landing the centre-back on a free next summer.
In addition to Quansah's possible move to Germany, there is also some uncertainty over fellow centre-back Ibrahima Konate's future.
France defender Konate has 12 months left on his contract at Anfield and is yet to agree an extension, while Joe Gomez's future is also unclear this summer.
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