morphing multiple meshes

Abao's icon

Hi all

A quick concept question... is there's a way to achieve the effect in my photo? particles within 2 mesh with different shape and morphing in flow motion? the flowing direction is not really matter at the moment, I am sorry for the rough sketch atm.
I am still trying hard to achieve it by gen and xfade, but this is really not easy, very very thankful for all kinds of advice.....

cheers

L

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