Lewandowski is leaving Barcelona this summer when his contract expires, and the Polish striker's departure has left a significant gap in Hansi Flick's attacking options.
Julian Alvarez, the Argentina international currently at Atletico Madrid, has long been considered Barcelona's top target to fill that void.
According to Catalan newspaper Sport, however, Barcelona are not prepared to pay more than €100 million for the 26-year-old, who is under contract at Atletico until 2030.
Atletico Madrid have shown little appetite to sell Alvarez, and the Spanish champions could be forced to look elsewhere if that stance does not soften.
That is where Kroupi enters the picture. The 19-year-old Frenchman joined Bournemouth from Lorient a year ago for around €13 million, and scored 12 goals in 33 league appearances during a breakout debut season on the south coast.
His form has made him the first teenager to register 12 goals in a debut Premier League season since Robbie Fowler in 1993-94, and Barcelona have been credited with strong interest as they plan for life without Lewandowski.
Bayern Munich, Paris Saint-Germain, Arsenal and Manchester City have also been linked with Kroupi in recent months, reflecting the level of attention his performances have generated across Europe.
Bournemouth managing director Tiago Pinto has been firm in public about the club's stance, insisting Kroupi is not for sale regardless of the size of any offer.
"Junior Kroupi will not leave Bournemouth," Pinto said.
"His contract still has more than four years remaining, there is no release clause, and he is not going anywhere."
Reports in Spain suggest Kroupi has not hidden his admiration for Barcelona and would be open to a move to Camp Nou, despite interest from Premier League rivals.
Bournemouth have set no official price for the forward, though earlier reports placed his valuation at around £80 million to £100 million given his age, contract length and the level of interest involved.
Sport's report suggests Barcelona's view of Kroupi's true value sits closer to €70 million, with the possibility of a player being included as part of any deal to bridge the gap.
For now, Kroupi remains focused on Bournemouth's preparations for next season, with any transfer talk likely to intensify only once Barcelona's pursuit of Alvarez reaches a definitive conclusion one way or the other.