"Trans" is latin, and means "across". "Vest"ite is related to "vestments", which is again Latin, and means clothes. The "ite" suffix denotes adherence and thus the whole word means someone who likes to dress in the clothes of the 'opposite'.
I reckon the questionner meant phonetic transliteration, as in "traenzvestait" (with the ae stuck together, the middle e written as a backwards 3, and the final i without a dot).