This study investigates how entrepreneurial characteristics and cultural diffusion affect the competency and competitiveness of international interns in the context of the "Ginou Jishu" internship program between Japan and Indonesia. The program aims to address labor shortages in Japan and unemployment in Indonesia by providing Indonesian interns with exposure to Japanese work culture. Using a quantitative research method, data from 400 internship alumni across 38 provinces in Indonesia were collected and analyzed using PLS-SEM. The study found that individual characteristics and Japanese work culture positively affect competency and competitiveness, with competency further enhancing competitiveness. Self-efficacy strengthens the impact of individual characteristics and Japanese work culture on competency and competitiveness, but weakens the effect of individual characteristics and competency on individual competitiveness. The findings suggest that the Ginou Jishu program, while improving non-work competencies, does not significantly enhance work-related competencies, which may hinder interns' performance in the workplace. The study also highlights the importance of self-efficacy in moderating the relationship between individual characteristics, cultural assimilation, and competency. Managerial implications include the need for tailored training programs that integrate Japanese work culture with interns' native cultural characteristics, building self-efficacy through mentorship and support systems, leveraging web intelligence for better decision-making, and aligning internship programs with Sustainable Development Goals.This study investigates how entrepreneurial characteristics and cultural diffusion affect the competency and competitiveness of international interns in the context of the "Ginou Jishu" internship program between Japan and Indonesia. The program aims to address labor shortages in Japan and unemployment in Indonesia by providing Indonesian interns with exposure to Japanese work culture. Using a quantitative research method, data from 400 internship alumni across 38 provinces in Indonesia were collected and analyzed using PLS-SEM. The study found that individual characteristics and Japanese work culture positively affect competency and competitiveness, with competency further enhancing competitiveness. Self-efficacy strengthens the impact of individual characteristics and Japanese work culture on competency and competitiveness, but weakens the effect of individual characteristics and competency on individual competitiveness. The findings suggest that the Ginou Jishu program, while improving non-work competencies, does not significantly enhance work-related competencies, which may hinder interns' performance in the workplace. The study also highlights the importance of self-efficacy in moderating the relationship between individual characteristics, cultural assimilation, and competency. Managerial implications include the need for tailored training programs that integrate Japanese work culture with interns' native cultural characteristics, building self-efficacy through mentorship and support systems, leveraging web intelligence for better decision-making, and aligning internship programs with Sustainable Development Goals.