In a reply to the comment below in this topic: difference between won't and wouldn't
If you ask me nicely, I will/would come with you. why here both will and would are correct?
The answer was:
Strictly speaking they're not both "correct". It should be ask + will (or asked + would for more "hypothetical" phrasing). But some native speakers in casual conversation aren't too fussy about such fine points. – @FumbleFingers
My listening skills may not be good enough, but I think I heard more than once in some animes where the characters use "would" with simple tense if-clause. Unfortunately I cannot bring up any evidence offhand. I sometimes capture some clips when I watch but I had to wade through hundreds of them if I were to look for a certain one.
Could it be true? I understand it is not grammatical, but, if so, what is it considered? Regional? Very informal? Slang?
Edit:
Maybe what I heard was something along the lines of what is in here First conditional with “would” instead of “will”
"If it rains tomorrow, I would go to the cinema" is conditional advice suggesting that the person you're talking to should go to the cinema in the case of rain. – Peter Shor