Looks like a fun project but as it's very similar to VanTien I'll probably stick with that, when I get time to keep working on it . Best of luck to whoever works on it.
Also @d3nniL you are correct, web games can use ANY key movement common to PC games in general. They can suffer from some ghosting issues but those are avoidable. So your question was good to ask.
You maybe know some webgame source like those with WASD walking?
I`m searching for such a webgame with WASD movement to translate.... that would be cool.