About the bear flag pattern, the diminishing volume during the formation is a must?
No, it isn't. However, in order to maximize your chances of winning the trade, you must use the volume indicator as your confluence. Some individuals use numerous indicators such as EMA and RSI in addition with a bear flag pattern. The more confluences the higher the probability. If you see a bear flag, you can utilize the EMA as dynamic resistance and the RSI for divergence. If you find these all in the chart, it raises your chances of winning the trade.
Hmm, everyone has his own preference, Moving Average seems to be more attractive for those only who are jumping in the market for the long run as whales, and patient holders as well, wining a trade is not at all granted a bit with any sort of pattern because as for particularly the condition in the market, we are facing its completely based on the developments related the market. Keep close eyes on the developments to win the trade with your analysis.