For underlying data access, yes. Anyone who has a Bloomberg terminal will be able to use OpenGamma out-of-the-box to access nearly any piece of Bloomberg data. Server-side Bloomberg data is also available via the Bloomberg Managed B-PIPE/Server API/SAPI service, although that will require some non-standard configuration. As long as you have permission from Bloomberg to access the data on that terminal and that data is exposed through the Bloomberg Desktop or Server APIs, the data itself can be accessed through OpenGamma, subject to any contractual restrictions you may have with Bloomberg (e.g. only using data on the same machine as the terminal). For specific questions on specific markets available to you, contact your Bloomberg representative.
Having said that, for emerging markets though, we may not support the standard conventions, curve and surface definitions in those regions out of the box for analytics purposes. New conventions, curves etc can easily be added, but it’s a case of finding the information. The standard conventions we supply are building towards full G20 support, with emerging markets coming later.