@JeremyECrawford
Slashing flourish use 'any other creature'. Does this mean you only deal extra damage to one other creature within 5ft or do you still damage each other creature like it does in UA?— xeno (@xenoexpert) November 26, 2017
"Any other creature" in Slashing Flourish means any other eligible creature—could be one or more. #DnD https://t.co/RCnLYklanK
— Jeremy Crawford (@JeremyECrawford) November 27, 2017
This is a case of poor wording which is inherently ambiguous.
It should have said “any other creatures” to refer to the ability to hit multiple. And it should have said “any other single creature” to refer to the ability hit only one.