Hello,
1/ Global settings you can find in Theme Options > Typography. Custom CSS code can be used also. Provide URL and temporary wp-admin access, and we will give you an example of code for the price.
2/ Theme options > General > Enable Old Widgets Panel > On, then go to Dashboard > Appearance > Widgets > Shop sidebar > Categories widget > Show hierarchy.
3/ Custom CSS code.
4/ https://xstore.helpscoutdocs.com/article/30-base-theme-translation
Regards