This thread is resolved. Here is a description of the problem and solution.
Problem: A variation won't be pre-selected for the translated product on the front-end if the attribute slug has non latin letters Solution: The fix for this has been released in the WooCommerce Multilingual 4.5.0. One small detail is that after we release this fix, the user needs to go to WCML > Status > Troubleshooting page and need to run the fixes for product variations.
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