You can use WPML or Polylang plugins

WPML

1: Translate Appearance >> Customize in WPML:

Go to WPML >> String translation >> Translate texts in admin screens

Find theme_mods_ireca or theme_mods_ireca-child

Choose option want to translate

Choose Apply Button: If save data is error, you have to increase input vars.

You can insert this code to .httacess in root site: php_value max_input_vars 10000

Go to WPML >> String Translation

2: Translate text, value in Custom field checkout: You can make these above steps, however you have to choose Ova CRS plugin

Read more here: https://wpml.org/documentation/getting-started-guide/translating-theme-options/​

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