I guarantee all of the countries on this list, both the Valley tech firms, and the Indian IT firms, have in-house counsel specially versed in this, making the process largely boilerplate.
When I moved to the US (to work for one of the companies on that list of tech firms), their attitude was "Do you need a visa?" (I didn't, as it happened) "Just let us know, we'll get you a H-1B". There wasn't any shadow of a doubt in their mind that it was much more than a formality.
It still about $6000 in filing fees and premium processing fees on top of the legal fees and meeting any other requirements the business has to meet to be in a place to sponsor them in the first place.
My experience with a large multi-national was that they outsourced all of the immigration work to outside legal firms. This firm hired a lot of immigrants, but I don't think it makes sense to hire full time legal immigration experts.
When I moved to the US (to work for one of the companies on that list of tech firms), their attitude was "Do you need a visa?" (I didn't, as it happened) "Just let us know, we'll get you a H-1B". There wasn't any shadow of a doubt in their mind that it was much more than a formality.