Hi Sergey! Hope you're doing great! Let's review some key points , based in my experience working with Latin American Startups(that sometimes/often are in a similar position) and also from a Web Design Agency that i own in a niche market what i can tell you is:
-The main issue from what you're telling is distrust, credibility, or skepticism and the best medicine against that is to show your work, there is no other way they're going to work with you , you're clients wants to feel secure about making the right choice , and the best way to do it is to show that you can solve their problems or fulfill their needs.
-Customers will always want quality service, that you treat them right and that your product or service give them something unique, no matter where you're from, so you should always focus in those aspects.
-If we all look to the origin of the startup ?, the ones as us that are in the "industry" , we may give a look to the origin , but it's rare that the general public is aware of that. So as long as you maintain great quality and service,
the market will favor you.
-About the forums, i think that you just landed the wrong people , opinion towards Easter Europe in changing in a good way, just to give you an example; we are all amazed with Estonia Digital Citizenship.
Finally, you should just go straightforward and land some clients in the Western World, begin with a niche or something small , until you have the credibility and strength to land bigger clients.
If you need some help with this last point, i will gladly help you with the strategy to land some clients in the western world in order to begin and grow your business there.