Dortmund are reported to value the 25-year-old at around €90million, with the German outlet suggesting the World Cup showing that saw Nmecha score one goal and register an assist as Germany's campaign ended in the round of 32 against Paraguay has only sharpened Liverpool's interest.
Nmecha extended his contract at Signal Iduna Park until 2030 back in March, though his deal includes a release clause that only becomes active in 2027, reportedly worth around €80million before falling closer to €70million the following year.
Liverpool are far from the only club credited with interest. Manchester United have also been strongly linked as they continue reshaping their midfield following the departure of Casemiro, while Real Madrid are said to have identified Nmecha as a potential reinforcement under Jose Mourinho.
Having progressed through Manchester City's academy before his move to Germany, Nmecha is understood to be open in principle to a return to English football, adding to the sense that a serious bid from one of his suitors could arrive before the window closes.
Former Premier League defender Robert Huth has backed Liverpool to make a move, telling Empire of the Kop that Nmecha's ball-winning qualities would suit Iraola's high-pressing approach.
"Felix Nmecha was one of the players that kind of stood out in the Germany team," Huth said. "He performed well; he kept winning the ball. I think he would suit Liverpool with Iraola as manager."
With Borussia Dortmund under no pressure to sell given the contract situation, any deal this summer would likely require a fee well in excess of the release clause's eventual value, leaving Liverpool to weigh whether to act now or wait for the price to fall.
The club's midfield options are also in flux beyond Nmecha's situation, with Curtis Jones expected to leave before his contract enters its final year and Alexis Mac Allister facing an uncertain long-term future at Anfield, both factors that could increase the urgency behind Liverpool's midfield business this summer.