William has been linked with Leicester, Watford, Tottenham and Monaco in recent weeks, and Wolves have joined that list.
According to Diario de Sevilla, Wolves have already made their first approach to understand Betis’ demands.
Nuno Espírito Santo has eight Portuguese players in his first-team squad at Molineux, including Rui Patricio, Rubén Neves and Joao Moutinho.
The heavy Portuguese presence is related to the super-agent Jorge Mendes who advises Fosun International, Wolves’ Chinese owners.
Betis are calm about the interest in William and will see how the season finishes before considering a sale. If they want to raise cash in the summer though, selling the 28-year-old would achieve that.
The La Liga club paid €25m for 75% of Williams’ sporting rights in the summer of 2018. That entitles his former club Sporting to 25% of any transfer fee.
William has a €120m release clause at Betis, a figure no team will be paying, but the Andalusians could consider a good offer.