Is ESA the same as a fixed deposit or ASB?

No, and this is the single most important thing to understand before you use it.

A fixed deposit guarantees a rate, is PIDM protected, and returns your capital in full. ASB is a unit trust with its own structure and a long track record of stable declared dividends.

ESA is neither. It is an investment product. The rate you see is a target based on the underlying instruments, not a promise. It is not PIDM protected. And the value can fall — usually slightly, but it can.

What ESA offers instead is a genuinely riba-free way to hold short-term cash. That is the trade you are making.