Most of the indicators for forex trading can predict the market movement, accurately on it's historical value and not it current action. Can any forex indicator predict market movement accurately?
Logically It's not possible to predict the price , at least nothing accurate as you are asking otherwise everyone would be rich by now. (this is valid for both fiat and crypto currencies)
If you logically think, no one will sell these working indicators to others instead they will keep it for them self and make lot of money. But they know that these are not 100% sure methods so they want to make money by selling these indicators instead of directly making money from indicators. It shows these are not 100% safe and don't trade on those indicators.