Mályvacukor (hungarian) - translates to mallow candy / mallow sugar

Just marshmallow in Brazilian Portuguese. Natives tend to pronounce it closer to something more like mah-she-mello, in my experience.

Malvavisco in Spanish as others mentioned, but in Chile we also call some varieties "guagüitas" (little babies) for some reason

There isn’t a word for it.

Vahukomm in estonian

Foam candy

I Italian they are just "marshmallows", but interesting enough, in the Ghostbuster film Italian's dub it was translated with "gnocchi di lichene".

Marshmallow (Swedish)

マシュマロ

Japanese

marshmallow or just shmalo

Esponjitas in spanish (Little sponges)

Some people also call them Nubes (clouds)

In Mexican Spanish they're known as "bombones".

chamallo in french sometimes. otherwise marshmallow