Dennis, who is on bail, is scheduled to face a hearing to answer those charges on Wednesday.
If found guilty of the first charge, he faces a maximum 15-year prison term and mandatory minimum 10-year licence disqualification.
The second charge has a maximum penalty of 12 months’ jail and a six-month disqualification.
He has made no public comment about his wife’s death.
Hoskins competed at the 2012 and 2016 Olympics on the track in the team pursuit, and was in the squad that won the 2015 world title in the event.
During his competitive career, Dennis won two world titles in the road time trial, and silver in the team pursuit at the 2012 Olympics and bronze in the road time trial at the Tokyo Olympics.
He became the seventh Australian to wear the yellow jersey as race leader at the Tour de France by winning the opening time trial in 2015, setting a race record for his average speed.
He also won the 2015 Tour Down Under in South Australia.
Hoskins was buried in her home city of Perth and a public memorial service was held in Adelaide in February. Dennis attended the service with their two children.
In March, prosecutors told Adelaide Magistrates Court police needed six months to complete a major crash reconstruction and four weeks to get the file to the Director of Public Prosecutions.
