1)
When were they handed over to nations?
1.
Rashi: In the days of the Shoftim, between one Shofet and another, e.g. Eglon, Kushan Rish'asayim, Sisera, Pelishtim and Midyan (ruled over them).
2)
Is "va'Yimshelu Vahem Son'eihem" the same as "va'Yitnem b'Yad Goyim"?
1.
Radak: Yes. The matter is repeated in different words.