I don't know how much research you've actually done yourself or you're just guessing, but check out the translation API.
I will give one example of the google API
You are charged for the amount of text that Cloud Translation processes, such as the text that you include in a detect language or translate text request. Note that if you don't specify a source language for the translate method, Cloud Translation detects the source language for you. You are only charged for the text that you provided; there's no additional charge for the detection in addition to the translation. For example, if you submit 1,000 characters for translation without specifying the source language, you are only charged for the 1,000 characters.
Prices are pro rata (proportional and incremental). Charges are scaled to the number of characters provided to Cloud Translation. For example, if you send 575,000 characters for processing within a month, you are charged $1.50. The first 500,000 characters are free while the next 75,000 characters are charged at the $20 per million characters rate.
Cloud Translation counts usage on a per character basis, even if a character is multiple bytes. Each character corresponds to a code point.
You are charged for all characters that you include in a Cloud Translation request, even untranslated characters. This includes, for example, whitespace characters. If you translate <p>こんにちは</p> to English, it counts as 12 characters for the purposes of billing.
Cloud Translation also charges for empty queries. If you make a request without any content, Cloud Translation charges one character for the request.
Now ask the developers how big is the chat volume every month on a whole fleet of servers and then come and say that money is not needed for this
If you want a translation, then you have to lighten your wallet
There is no such thing as a free lunch - an old Estonian saying