Translation:Éva sings in front of the Polish tourists.
Phew, why do you word it like that? Are you trying to reflect the Hungarian word order? It doesn't work out really well, because you end up with different grammar (instead of present continuous "is singing" you end up with simple present "is" and a present participle clause) and a slightly different meaning.
I think your variation could be translated more accurately as "Éva a lengyel turisták előtt van, énekelő."
EDIT: Please disregard the last sentence. jzsuzsi has better insight. (Nov '19)
énekelő is not good here. You would use it in a phase like "az énekelő kutya" " the singing dog"
Eva is in front of the polish tourists singing" can be "Éva a lengyel turisták előtt van/áll, énekelve" I think that is grammatically correct, but still sound pretty unnatural to my ears. Maybe rephrase it as "Éva a lengyel turisták előtt van és énekel. "