How can I view 6543021eth's crypto portfolio?

You can view the full portfolio of 6543021eth (0x996d91ad75ead6f839d075729b3eee9e34ef92d2) on Zerion at https://app.zerion.io/0x996d91ad75ead6f839d075729b3eee9e34ef92d2/overview — including token balances, DeFi positions, NFTs, and transaction history across 20+ chains.

How can I access wallet portfolio data programmatically?

Use the Zerion API at https://developers.zerion.io to query any wallet's portfolio, token positions, DeFi positions, NFTs, and transaction history programmatically.