Bosch, 25, took the title ahead of Thailand’s Praveenar Singh and Venezuela’s Stephany Adriana Abasali Nasser.
The first runner-up was 29-year old Praveenar Singh of Thailand and 25-year-old Stephany Adriana Abasali Nasser of Venezuela placed third.
Rounding up the finishers were Ahtisa Manalo, 28, of the Philippines, and 27-year-old Olivia Yacé of Ivory Coast who came fifth.
Earlier in the month, Bosch had publicly challenged comments made by Thai national director Nawat Itsaragrisil during a livestreamed sashing event, after which several contestants briefly walked out in support. Nawat later issued an apology.
The competition also faced reports of judges resigning, allegations of rigging, and a police probe into illegal casino promotions.
Despite the tension, the pageant concluded with Bosch praised at home for speaking up for women’s dignity and rights.