Both are based during Japan's colonization of Korea and in the future. Both have jumpcuts between main character when they were a kid during Japan's colonization and main character right now, when they're old and wrinkly.
They're both about comfort women and the horrific ordeal they went through. Spirit's Homecoming, however, is much more graphic when describing and showing the abuse the young girls were subjected to.
Both movies are about comfort women. Snowy Road showed more detail about what happened to the women during the war, whereas I Can Speak showcased the fight to gain acknowledgement from the Japanese government. Both are heartrending depictions.