The government is populist and very bad, but on this matter it's actually pro-Ukrainian. They gathered support creating anti-Muslim histeria, Ukrainians shouldn't have any problems with that.
Ukrainian and Polish are very similar languages and after 1 year you can learn the other one and speak with no recognizable accent (my cousin's wife is Ukrainian and nobody realizes that till she tells them).
There are nationalists that do have problems with imigrtion from Ukraine and Russia, but they are a marginal minority, not unlike the nationalists in UK protesting Polish immigration. They don't represent the mainstream opinion and aren't a threat in 99.99% of situations.
