..quick Question..

Charc. is former member of Wuxing's Armed Medical Team.
Obivious language is Cantonese ( got it in rating 4)
Would Mandarin-chinase also be requied language to work for them..
same rating, lower, not at all?..
options needed..

I'd say it depends where he's from. If he's from the UCAS and been working with Wuxing UCAS for his whole life, he can just speak English (maybe with a "Wuxing corp-speak specialization") and have 1 point in Cantonese because of a few Cantonese words that were commonly used in the workspace.

Unless he was a high-level manager, I don't think the corp would expect him to speak Cantonese or Mandarin. The boss's inspirational speeches can be translated.

..charc. is from Boston, Ucas. descreption of Wuxing is all employees are familiar w/ chinase culture.( That includes Mnadarin language?..)
position was/is security for Medicos / Client ( Corp. street samurai..)

Knowing Mandarin assumes that that is the default language spoken. While Mandarin is the default for China in our world, the China of Shadowrun is no more and has broken into several separate countries. Each could have their own language (Cantonese, Shanghaiese, etc) based on location. Wuxing is based out of Hong Kong and Cantonese is spoken there as much as Mandarin is. I can't remember if they ever said which was the default for Wuxing but you can easily make an argument for either language.
Depending on which edition of SR you are playing, language chips are cheap and easy to get so they could be another option.
Ask your GM if he has a preference and just go with that.

Edition is 4ed
Corporate Guide (p. 178) sayss .prrimary language: Cantonese, Secondary is English.

Well there you go, you don't need Mandarin. As this is for 4th ed, you can get by with language chips if it does become important.