I have written a plugin for speeding up latex math typing in obsidian which works rather similarly to the syntax in word equation. Was wondering if it might meet your need?
The plugin can be found in community plugin list with the name “quick latex for obsidian”
there are quite a few handy functions such as autoFraction, where you can type 1/2 followed by a space key and it will be replaced with \frac{1}{2}, very much like how it works in word equation~
There’s a plugin for Sublime Text which is called Unicode Math.
You simply type a backslash (\) and then you follow it with either a Unicode code, or a shortcut, either pre-set or one you define yourself in the config file. I use it almost every day for special characters, especially when writing Norse language texts, or other quaint stuff. It’s pretty great, and I sorely miss it in Obsidian.