Hey! Hope you don't mind if my feedback is long and critical, since you submitted it a lot of places, I can tell you're really serious about getting lots of feedback to work on this particular game, so I hope this can help you improve. I think it's very well polished and a solid prototype, for the record. I like this game a lot.
UI Stuff:
-Game launches in the top left corner of my screen and is slightly cut off. I'm not able to drag and recenter it, or fullscreen it, or access the title bar. On Windows. I have 2 monitors that are both 1920 x 1080.
-The font makes it hard to tell what the characters I need to type are sometimes, as it's very angular and its kerning is pretty squished, and they're hollow inside, making the lines confusing. I couldn't tell what Q was for at least 4 games, and it takes me a longer time to figure out U vs V or O vs D for example.
-It should also be made clear that everything must be typed in uppercase, or otherwise have it not matter. I would prefer it not mattering so that people don't need to hold down shift or use caps lock.
-The characters you have to type are rather dark and don't stand out as much as they should. This could be due to my window being off centered and so they're very hard to notice, though.
-Generally it would be nice to have consistency in art style. If the sprites are pixel, try to keep the text a similar style and the background as well.
-The player's eyes will always be glued to the top of the screen to see the incoming characters, making everything going on below basically pointless no matter how nice it looks. If you changed it to be centered on the game screen or added moments where the player can afford to look at the flashy animations without possibly losing time typing, then it would be better.
-Similarly, the player won't be able to tell when they've made a typing mistake because their eyes are nowhere near their input and wrong characters aren't highlighted red, and that can be very costly.
-The gauge decreasing doesn't always make sense. The opponent attacks midway through the gauge or earlier depending on the exact phase. I think the gauge should flatly represent how much time you have left to type, or else it gets confusing.
-Mild nitpick: I thought the "minutes" in the end was "meters" lol so I think the more traditional way of expressing it using colons like 1:00:00 makes more sense
Gameplay experience stuff:
-The LRN screen is mostly a wall of text, and hard to absorb after just one reading. If you ever have time, programming a turn by turn tutorial would be very useful.
-Similarly, the LRN screen doesn't actually teach the key basics of gameplay, it goes into score detailing which doesn't matter to a newbie. I think something saying that when you have characters at the top you need to type what it says, but when you see a number in the middle you can write whatever you want to fulfill that number, would help.
-On my first playthrough, because it was cut off at the top, I couldn't see the phase names and I had no idea when I was supposed to be typing the phrases and I kept taking damage while having no idea what the decreasing gauges meant.
-Gameplaywise, just spamming random characters to get to the character limit during attacks isn't very fulfilling. To make it more fastpaced and increase strategy, similar to what the commenter below said, maybe making the attacks also be phrases similar to the ultimate moves, and what you type during that phase determine your next move, would add strategy. such as DODGE STAB JUMP BLOCK etc. being the phrases you need to type, and instead of each phase being based on character length, it would just increase the number of actions taken during each round, if that makes sense.
-I don't get what's happening in the AvR stage. I hit A or R, but nothing happens and I always end up taking damage. Same with first blood. I type out the full phrase, it disappears and nothing happens, I have to retype it, and I never get an ult point.
-The suggested WPM/CPM is slightly misleading, because typing random characters that just appeared will always take much much longer than typing out known words, and most people know their WPM, not their CPM, but their WPM is almost halved in this game. I thought Copper was WAYY too hard for my WPM level. And my WPM is 150. I can't beat Wood due to the AvR stage.
Overall, I think this game has a lot of potential as a new take on a turn based fighting game and I would love to see further changes made to it! I had a lot of fun and *would like to* beat the hardest difficulty!