The 20-year-old was a key player for his Portuguese club during the 2021-22 campaign, making 45 appearances in all competitions, contributing five goals and three assists in the process.
Inacio still has more than four years left to run on his contract at Sporting, but there is believed to be a €45m (£38.5m) release clause in the agreement, which has led to a host of speculation.
Man United are said to be interested in signing the centre-back this summer and would allegedly be willing to pay the buy-out fee in full.
However, according to A Bola, there is also genuine interest from Barcelona, with the Catalan outfit prepared to rival the Red Devils for his signature in the current market.
Inacio has been with the Green and Whites since 2012, progressing through their various youth teams before making his senior debut in 2020.
The Portugal Under-21s international has made 70 appearances for his current side in all competitions, contributing seven goals and four assists, and he featured on seven occasions in the Champions League last term.
Barcelona, meanwhile, are also expected to sign a centre-back in the current market despite the arrival of Andreas Christensen on a free transfer, with Clement Lenglet, Samuel Umtiti and Oscar Mingueza likely to move on.
There has recently been uncertainty surrounding the future of Gerard Pique, with the former Spain international's position at Barcelona called into question.
Pique struggled with injury problems last term, missing the final four league matches of the 2021-22 season due to an abductor issue, but he did make 39 appearances in all competitions.