Using the MACD for counter-trend signals is likely to lead to losses and more difficult trading experiences than you would like.
With the downward channel indicating a downtrend, and if you were to look for MACD crossover below the zero line, to signal a buying opportunity...
The first 7 buying signals show price climbing briefly/slowly to the upside but reverses strongly.
Only in the last example, as price bounces off the support of the channel and a brief shift in fundamentals led to the trade climbing to the TP level.
Remember: Countertrend trades have a 70% chance of failure. If you are relatively new to trading, look for trend-following trades first.
In fact, even if you are an experienced trader, trend-following trades should still be the primary/idea set up.