I cannot use ！ as a synonym for 感嘆符. Or rather, I can add it, but it is rejected by the “you accidentally entered Japanese when you should have entered English” shake when I enter it as an answer. On the other hand, ! does work.
I think an exception should be made for ！
Have you tried it with the normal exclamation mark instead of the full width version?
See my first comment!！
I know you used ！, but what stops you from using ! instead? That would circumvent the whole problem. It seems a bit unnecessary to adapt a whole system to use ！instead of ! when they are the same thing. Maybe I’m just not seeing the reason, but it seems like you are making it more difficult for yourself than it needs to be.
It requires switching keyboard layouts.
For once i am in the complainers camp. I’m regularly frustrated to not be able to put Japanese as User Synonym if I want. And I mean generally, not for this particular case.
You don’t need to use the Japanese keyboard at all on WaniKani - it’s got its own IME, so you can just use the English (or whatever) keyboard for all answers.
I am well aware, but I would like to use a Japanese IME. It gives me the opportunity to learn it.
Hang on, do you want to change the Reading synonym to an exclamation mark? The main point of the vocabulary is not to teach you vocab, but to enforce the reading of the kanji you’re learning. By changing that to ！, you don’t enforce the reading of that specific kanji.
No, no, just the meaning.
Let me be extra clear. If my current IME method is set to Japanese, I would like to enter ！. If it is set to English, I would like to enter !. Both of these would be for the meaning. It would save me from having to switch the IME method in this particular case.
Not really the solution you’re after, but both my phone and my desktop include the half-width mark as one of the conversion options for the full-width one - does that not do the trick?
Oooh that makes a bit more sense. I guess that would make sense.
Kind of. The problem is it really difficult to tell them apart.
Oooo! Do you mean like using a JP synonym that you know really well? That would be really cool actually! I’m coping with English translating but it does get annoying when I’m reading and all I can think of is the English word of each individual kanji.
edit: I’m realizing now that I would then only think of its synonym but not it’s actual reading, nvm 
There are many cases where i’d like to type a jp word instead of anything else because i’m already familiar with it and I do not want to reinforce the connexion with english but the current system just block jp input which is frustrating.
The best example would be to add the kun readings with okurigana of some kanjis (verb training !) instead of the english meaning that I freaking know.