For information,
The name "Soini" is currently documented as "Finnish feminine form of SVEN". However, the name is definitely masculine. The name service of the Finnish Population Register Centre at https://192.49.222.187/Nimipalvelu/default.asp?L=3
gives the statistics as follows:
soini
Years of birth Men Women Total
-1899 5 3 8
1900-19 299 42 341
1920-39 596 83 679
1940-59 374 12 386
1960-79 85 0 85
1980-99 25 1 26
2000-04 4 0 4
2005 1 0 1
Total 1389 141 1530