Can someone help me with a tool / software that can trigger emails whenever a RSI breaches a 20 or 70 level mark?
You can find the same option in money control .whenever trigger breached certain level we will get trigger/mail from the site.
You can simply create a spreadsheet to do that work. Fetch the historical prices from =googlefinance(“ticker”) function and run the prices with the formula needed to calculate RSI or something. For alerts, you can use Google App script to get notified (emails alerts).