Trade Companies in vanilla:
The "Wealth of Nations" DLC is essential for the functionality of trade companies. This expansion introduces the ability to create trade companies, which are organizations that control trade in specific regions outside of Europe, increasing trade power and providing other benefits.

Forming the VOC (Dutch East India Company) in vanilla:
Forming the VOC is part of the "Dharma" DLC, which focuses on the Indian subcontinent and includes various features related to trade companies and colonialism. With this expansion, Dutch nations can form the VOC, gaining special bonuses and missions.

To fully utilize trade companies and form the VOC, ensure you have both the "Wealth of Nations" and "Dharma" DLCs for Europa Universalis IV.