Trapp, 30, is actively looking for a new club and Eintracht are not against selling him.
Betis have been given the chance to sign Trapp with new head coach Manuel Pellegrini looking for a new goalkeeper.
Hertha Berlin are also showing interest but it is unclear whether they want to pay the €7m-plus asking price.
Trapp signed a five-year contract with Eintracht in August 2019 and became a top earner with an annual salary of just under €5m.
The Coronavirus has impacted Eintracht heavily though, and they need to cut the wage bill by around €20m to €50m.
Three-time Germany international Trapp joined Frankfurt from Paris Saint-Germain for €7m last year after a successful loan spell.
Trapp was previously on Eintracht’s books between 2012 and 2015 before PSG took him to France.
He is the undisputed number one at Frankfurt but could be about to say farewell again after just one year.