If you're aiming to earn $3,000 a month in cryptocurrency without engaging in trading, here are some legal and viable strategies to consider:

1. **Long-Term Investment**: Allocate your funds into established cryptocurrencies like Bitcoin or Ethereum. Focus on projects with solid fundamentals and growth potential. This approach requires patience, as significant returns often come from holding your investments over time.

2. **Staking**: By holding certain cryptocurrencies in a wallet to support the network, you can earn staking rewards in the form of additional tokens. Numerous projects offer opportunities for staking, allowing you to generate passive income.

3. **Cryptocurrency Mining**: With the appropriate hardware, you can mine cryptocurrencies by validating transactions and solving complex algorithms. Keep in mind that mining can be costly and demands significant resources.

4. **Decentralized Finance (DeFi)**: DeFi platforms allow you to earn passive income by lending your crypto assets or providing liquidity to decentralized exchanges. This can result in earning interest or transaction fees.

5. **Freelance Work in the Crypto Industry**: Offer your expertise in areas such as content creation, marketing, development, or consultancy within the crypto space. There is an increasing demand for professionals skilled in cryptocurrency and blockchain technology.

Achieving a monthly income of $3,000 in crypto requires thorough research and consistent effort. Stay updated on industry trends, explore various income streams, and always manage your risks carefully. Best of luck on your journey!