Stay away from mixers, I have a friend you lost some ETH when trying to use mixer, I don't even want to know if the mixer is real or not if you want to avoid track or tracing use dex exchange
Your conclusion is same as
- Don't invest in bitcoin because friend lost money by invest in PONZI scheme that use bitcoin as their tool.
- Don't trade on crypto exchange as my friend lost his crypto on a scam exchange.
Choose good tumblers and you will have bigger prob to be fine rather than to be scammed. Give your friend two topics and ask him to check any tumbler in the future.
Some explorer tools can be use to connect ETH addresses and transactions, you should know it:
https://ethtective.com/https://blockchain3d.info/how-to-use/: will support ETH soon.
(Compilation) What is the best Ethereum explorer