In short: Drinking fruit juice by a healthy person with a normal kidney function do not likely have any significant diuretic effect.
Even if you drink, let's say, 2 liters of 10% fruit juice within 30 minutes, it would likely take about 2 hours for all the juice to be emptied from the stomach into the intestine and absorbed into the blood. Sugar delivered from the intestine will gradually increase blood glucose, but this will be balanced by the glucose taken from the blood by the cells, so, the blood glucose will not likely exceed 11 mmol/L, when glucose can start to move from the blood into the urine and cause diuresis.
I can back up this by the glucose tolerance test in which you drink 1 cup (237 mL) of a drink with ~35% glucose (>3 times as much as in a usual fruit juice). 2 hours after the test, the glucose levels in a healthy person (without diabetes mellitus) will be lower than 7.8 mmol/L, so below the diuretic level (11 mmol/L).