Your scenario involves routing calls based on language spoken.

Omni-Channel routing with skill mapping based on agent language proficiency is the most effective feature for routing calls based on the language spoken. This feature allows calls to be directed to agents who are proficient in the language required by the caller, ensuring effective communication and enhancing customer satisfaction.

References: https://help.salesforce.com/articleView?id=sf.omnichannel_skills_based_routing_setup.htm