Should I do Check ride in A320 SIM as an LPC or Fly King Air B200?
The B200 type rating in the US isn't required, as it's under 12,500 lbs. No type rating required. Unless you're flying a variant with a weight in excess of 12,500 lbs (C-12, for example), one won't be issued, either.
Yes it is.
Your will have a limitation stating " Single engine Commercial priviliges only" or something similar.
Close. The FAA issues certificates, rather than licenses. Whether it's the ATP or commercial, it's still just one pilot certificate, with various ratings. Ratings are had in category and class, and may be held at various levels of privilege.
One may hold a pilot certificate with ATP privileges for Airplane, Multi-Engine Land, but at the same time hold on the same certificate Commercial privileges for Airplane, Single-Engine Land.