I did master in finance and i am having 5 year experience in accounts & finance.
Then I think your chances are not that bad if this is the case.
As i said i don't know polish language's but i know english very well.
I would rely more on Belarussian than English in Poland in your everyday life. As a Pole I can pretty easily follow the news or films broadcast on Belsat, a TV channel in Belarussian financed by the Polish government (btw, it is extremely funny to hear all their commentators speaking Belorussian, whereas people in the streets interviewed by TV Belsat crews almost exclusively speak in Russian). There is a growing numbers of Ukrainians working in Poland due to the increasing shortage of domestic labour force in Poland, but also a (much smaller) number of Belarussians is reported. It shouldn't be difficult to learn Polish for you given that you are already well accustomed to the Latin alphabet.
In the world of finance English is of course a very big advantage, but reasonably good Polish is necessary if you are thinking of a "good job" in Poland