Justice League x Hero! Reader Scenarios

If you speak a language they don't know

Superman:

It made his eyebrow quirk up, suspicious as he thought he had heard most languages so he tried to think which language this is then asked you. This is part of you and he wants to know and learn every part of you, so he asked you to teach him. So while doing things, like cooking, he'll try to ask you for items by saying the simple basic words, not able to do the complex words or sentences yet but slowly he is learning.

Batman:

He was surprised as he knew most languages. At first, like any new language, he wanted to intensely learn it so he immediately knows it all. But he found an odd joy in hearing you speak it and having no clue what it means; a mystery to solve and to learn it tiny bit by bit by hearing you speak it. So he did not learn it by himself and instead took his time learning it via you.

Wonder Woman:

She likes learning new cultures; though can be quite truthfully blunt about her thoughts on them so when she heard your language she wasn't shy to say her truthful thoughts on what she found of it. But she still wished to learn it and discover more of where this language came from. She definitely wishes to pay the place a visit once you teach her enough words to get by.

J'onn J'onzz:

He recognized it so he said the name of the language. When you nod and asked how he knew he told you where he once heard it and how it interested him even then so he would like it if you taught it to him. So each day both spend a few minutes just talking in the language so he can learn. He likes learning this of you and the culture where it came from.

Flash:

He ran off to go gather his research materials then threw them on his bed then returned to you. That evening he hyperfocused on learning this language. The next day he took your hand, gave it a kiss, and flirted in your language.

Hawkgirl:

She laughed when she first heard it, so surprised by this discovery then tried to repeat the words but failed so miserably. She asked you to say it again then she tried to repeat it again, a bit better but still bad. So each time you spoke it she would repeat it, and not to just be silly but mainly to learn it as she would repeat it slowly and try to think what it could mean and remember the words.

Green Lantern:

He doesn't like it because you damn well know he doesn't know so you are either doing it to annoy him or to tease him without him knowing. He does like it and find it funny when you start talking it without realizing or get so angry you switch to that language. So he picked up only the curse words.