An adult shop manager has faced court for allegedly trafficking synthetic cannabis across regional Queensland, after the investigation into the deaths of two men in Mackay last year.

The two men died in separate cases last January and another 31 were hospitalised after smoking Full Moon tea, which police allege was sold in the stores as synthetic cannabis.

David Andre Jules Piccinato, 43, was extradited from Melbourne on Thursday, but a decision on his bail application has been set aside for another week.

The court heard Piccinato operated five adult shops across regional Queensland, including in Bundaberg, Rockhampton, Mackay and Toowoomba via a live camera feed to his family home in Melbourne.

Police allege he profited $2 million from selling the alleged synthetic cannabis since investigations began last year.

In an affidavit tendered to court, police investigators said the alleged synthetic cannabis was still being sold throughout stores until last week.

Piccinato's lawyer, Adam Magill, told the court his client willingly followed the extradition request and would surrender his passports if he was granted bail.

He added the exact chemical compound of the products being sold were yet to be tested before the court.

He also said it was "farcical" to suggest Piccinato was part of a drug trafficking syndicate, since he was the only person to have been charged in 12 months of investigations.