AFAIK, definitely.
What determines whether he counts as a foreigner then? It seems like having citizenship should make him Japanese. Is it because he has chosen to represent a foreign country?
Another thread mentioned that he already had a Japanese passport, and was raised in Indonesia. If he already has citizenship, there shouldn't be any visas required.
So looking at the weight difference between then and now, I'm left wondering what spurred the increase. Were the rikishi in the 1800's also full time, or did they have lives outside of Sumo? Did the level of competition increase in the 20th century, pushing the weigh class higher and higher? They don't look more than 100kg.