Does adsense approve regional language blogs or web site?

Earlier Google Adsense was limited to a few global languages but slowly they included more languages and out of the Indian languages they have now included some of them. Presently the Indian languages accepted by Google Adsense for their revenue sharing program are Hindi, Bengali, Urdu and Tamil. I think one can monetise ones blog or site contents after getting the specific approval of Google Adsense for that language.

Anyway, there are some other networks also like Media.Net, BidVertiser, and Chitika etc which also one can explore for monetisation of contents posted in the regional languages.

Yes. Google Adsense scheme is being extended to the regional languages blogs and websites. I understand that recently Telugu is also added to the list of languages that are being accepted by Google for Adsense in addition to Hindi, Bengali, Urdu and Tamil. But the process of getting approval is a little difficult these days as there are many blogs and websites and all are trying to apply for this programme and so Goggle is not showing much interest and they are taking their own time in accepting it. In the coming days, it will be further difficult. There some other institutions like Google which are offering a monetisation programme. Those can also be explored.

Does AdSense approve regional language blogs or website?

Yes.

How to get approval from Google AdSense for a regional language website?

There is no different procedure for the regional language's AdSense approval process. Google approve / reject for all (the accepted languages) with almost the same parameters. Google never reveal its complete process though.

Apart from English can any one apply for other language websites in India for example Bengali, Kanada, marathi etc.

Yes, any regional (recognized / listed) language website can apply. It is again with the same procedure whether to approve or reject like an English language website.

Does it minimize any revenue as the viewers limited from particular state or region?
It is again depend on few valid click even from the less views with the better CPC of an ad bid in local can result reasonable revenue. And higher traffic with huge ad click against the local ad bid (higher or low) price and CPC may vary. In case ad bid is less and the traffic is higher without click then the website owner will get reasonable 'page impression' revenue as well. Such different scenarios on this.

Does Google show the same English ad or they have also regional content ad to show?
There are few regional content (Hindi and other languages) ad comes often those requests placed by the 'Advertiser' and will help the regional language 'Publisher' (AdSense member). Again, it is depend on natural traffic and valid click with the bid price / CPC, done.

Very recently, I have come to know that Bengali, Hindi, Tamil and Urdu blogs are accepted for AdSense Revenue. However, I am not fully aware of the details.