There has been speculation about interest from several clubs throughout the year, with Barcelona and Tottenham both mentioned as potential destinations for the forward in recent months amid the ongoing uncertainty.
Should the Guinea international leave Signal Iduna Park, Borussia Dortmund will need to find a replacement, and two names are understood to be on the club's wishlist.
According to German newspaper Bild, Kosovo international Fisnik Asllani is Dortmund's top-priority striker target this summer.
The 23-year-old made his breakthrough in the Bundesliga last season and has also attracted reported interest from Chelsea and Bayern Munich.
Asllani plays his club football for TSG Hoffenheim, and his contract with the German club runs until the summer of 2029.
Should a deal for Asllani prove impossible, Dortmund are instead expected to turn their attention to Folarin Balogun, according to the report.
The 24-year-old is expected to leave AS Monaco ahead of next season and is contracted to the French club until the summer of 2028.
Balogun has also recently been linked with Chelsea, Newcastle United and Barcelona.
Guirassy has established himself as one of the most prolific strikers in the Bundesliga since arriving at Dortmund, and any departure would leave a significant gap in Niko Kovac's attacking options.
Asllani's rise has been rapid, having spent time on loan in Austria and the second tier of German football before establishing himself at Hoffenheim, where his form has now attracted interest from some of Europe's biggest clubs.
Balogun, meanwhile, has struggled to hold down a regular starting place at Monaco and is seen as a player who could be available for a reasonable fee this summer.
Dortmund's pursuit of either forward would depend heavily on the size of any fee they receive for Guirassy, should his exit from Signal Iduna Park be confirmed in the coming weeks.