I've seen mixers for altcoins in the past, but can't tell you if they're reliable.
There are plenty!!! ... but all of them are scams.
Interesting. I wonder what is ROI, daily/weekly volume etc in case of BTC mixers and how it is related to the market cap. Entry threshold? Do these numbers make altcoins mixers unprofitable or there is just no need for them? BCH has around only 0.5% of BTC market capitalization, but is it the answer?
If we keep in mind that chipmixer was able to pay thousands of dollars per week for promoting their business on this forum, then we should assume that their volume and income is very high. According to news websites, it's believed that more than 150,000 bitcoins have been laundered on chipmixer. They weren't chargin regular fees, like 0.5%, 1% or something like that, they were absolutely free to use but instead they had fixed chip size, for example - 0.001 BTC chip, 0.002, 0.005, 0.01BTC, something like this. So, if you were to deposit 0.0012 bitcoins, you would get 0.001BTC and 0.0002BTC would be a donation from your side. Also, in order to increase your anonimity, you could lessen your bitcoins by donating some of them, probably a lot of people were doing that. They were also offering provably fair betting with chips. So, yeah, they had a great business model and were making tons of money.
Majority of exchanges charge fixed fee and also let you to choose certain range of fee in order to increase your anonimity. I bet exchanges should be earning between 1-3% from each deposit. It's a pretty good business even with a weekly volume of 10 BTC.