The questions that deal with language errors during peer-review (1 2 to name a few) typically recommend suggesting the authors seek proofreading help from a person who is proficient in English. From my experience, it feels that most non-native speakers have no connection to such a person, and so their manuscript will keep the very same errors and get some more.
Luckily, quite a few of the language errors can be eliminated using proofreading software like grammarly or languagetool. My question is whether it is acceptable to suggest these tools in the review? How explicit can the recommendation be ("The authors should use proofreading software" vs "I'd suggest the authors to use grammarly.com")?
My apologies for the language errors! :)