How can I obfuscate my writing style when I review papers?
It's not worth it. Few waste time trying to unblind their reviewers to take retribution for bad reviews. It's just not worth it. The average journal submitter doesn't have enough power to do damage to a random reviewer. 

If you need a strategy, trying passing your text through Google Translate to Spanish and back to English. It'll probably be garbage afterwards, but it'll definitely lose any idiomatic turns of phrase that might identify you.