All areas are different. Around me, the following names seem to be duplicated a lot:-
Noah
Oliver
Oscar
Archie
Teddy
Leo
Arlo
Jacob
Harrison
Grayson
Roman
Caleb
Olivia
Isla
Sophia/Sofia
Evie
Freya
Willow
Phoebe
Sienna
Aria
Hallie
Harper
Maya/Mya
Mila
Luna
Some of those are very popular on a national level, others I feel some of those parents were perhaps trying for a little less usual and may end up disappointed when they realise their child is actually one of many at their school/in their area (Luna, Mila, Aria, Grayson, Roman, Caleb etc).
Yet I hardly ever hear Isabella, Ava, Poppy, Lily, Ella, Elsie, George, Arthur, Jack, Freddie etc around me, all of which are apparently very popular on a national level. So you never can tell. Better to just go with what you love as it really is pot luck as to whether it will be duplicated in the playground or not.