"I have an instance where someone is using "English" (probably not AmerEnglish) words when writing and I wondered if these ... etc. ... .) (2) by for bye ( Never have read it anywhere ...) (3) don't worry for don't fret."
(Don't misunderstand jokes, ever!)
(1) Common enough in Scotland, but only in spoken English. A former registrar, a Scot, Margaret Love, however, left me colloquial notes, saying, 'Afore I left ... Don't fret, John, we have placed Manlio with Mrs Gibbons ( a student placement.). You could hear her talk via her memos!'. Wonderful!
(2) Unknown.
(3) Very common in Ireland. ('frettan' is ME for 'consume', so don't consume yourself in worry or grief, so 'Don't worry!'.)
foolsrushin.
"I'd have to do some difficult research to find more examples."
You could look at Henry Sweet's 'Anglo-Saxon Grammar.' It is thought that he was the model for Henry Higgins - in Shaw's 'Pygmalion,' transformed by Lerner and Lowe into 'My Fair Lady.' At one point, they began to regret their attempt to do it, notwitsanding their love for the plays of Shaw.
http://www.metacafe.com/watch/883791/my fair lady/
foolsrushin.
PS: In Hartford and Hampshire, hurricanes hardly happen ... .