One of the highest-profile options is Lossless Aegis. This business-to-business tool monitors blockchain transactions and flags suspicious activity by scanning all transactions in newly mined blocks as they're created. It combines that data with machine learning algorithms to spot patterns and predict which addresses are likely to be involved in problems, and it's designed for companies that want to improve security before problems show up.
Another tool is Web3 Antivirus, a free, open-source browser extension that's designed to protect the Web3 ecosystem. It blocks people from signing transactions that are likely to be malicious and from interacting with assets and phishing websites that could be malicious. Web3 Antivirus includes risk assessment, transaction simulation and a large blocklist to block known malicious sites, so it's a good option for those who want a safe and trusted option.