Im retired so I will give you a few clues how you can improve your game.
Do you talk about heads up cash or heads up GTO?
HU Cash:
Its played mainly 100bb deep.
At this stack depth you dont have a open shove range.
HU Sng:
At around 15bb or less there are combos that a GTO strategy would open shove. But GTO will limps with the majority of combos. At around 8bb you will find a lot of open shove combos. Your Nash chart from above is for HU Sngs ans not for HU cash. In Sngs you have pre and postflop no rake in HU cash you have rake so the ranges would be different.
Nash Charts:
People have used these charts at around 15bb or less to open shove some combos. These days people lean towards GTO. Just because a nash charts says that a open shove with 20bb or more is +EV it does not mean that you should do it. Just playing accordingly to a Nash chart is not ptofitable.
Never try to copy a GTO strategy because its not max. EV. You can use it as a guideline and vs. unkowns or very strong player. But remember even world class players have leaks. You need to understand how/when and why you can/should avoid GTO plays.
For HU Cash: Visit upswing poker and watch the free Doug Polk analysis. Its free and good content.
For HU Sngs: Thats the format where I have played most of my volume. There is no good free content as far as I know. Most of the time you will find only old learning material. You need to use your own brain in this case.
General advice: You can learn alot from GTO solvers if you understand how to use them.
You get GTO preflop ranges and study them. Visit gtowizard.com for free GTO ranges. Try to understand why GTO plays how it plays.
Most HU cash GTO ranges are solved for NL500 rake. If you play NL10 HU Cash you will play with a higher rake so you need play tighter.
Another tipp dont join players that are open sitting unless you have a big edge against them. Dont reg battle on micros because the rake is to high. In general you should never reg battle if you want to make money. You can reg battle for learning purpose.
I hope that helps.
