I'm not sure that would have made a difference. Lee was planning on dividing the army into three corps before Chancellorsville. Ewell would still have commanded the third corps and would likely still have come in from the north so his failures on the Union right would still have happened. Jackson likely wouldn't have done any better than Hill on the first day, and after that Lee exercised control
Ewell replaced Jackson after the latter died in May. Ewell failed to follow up his victory of July 1, and then let the Yankees entrench on Cemetery Hill. Jackson NEVER would have made that mistake, and would have taken and secured the high ground.