I've said for many years that the language barrier is a major factor in keeping Japanese workers from earning pay in global markets that's more commensurate with their abilities. If more Japanese workers were more competitive for global jobs, there would be more pressure on Japanese companies to improve their working environments and compensation. But there was the Bubble and the domestic focus of Japanese companies to distract.
Unfortunately, many other nations have become very competitive in English proficiency now. 1980s-2010s was the period to build an English-proficient workforce and enjoy the economic benefits (as my country Singapore did decades ago).
Keep trying to apply for jobs in companies or countries with better working cultures.