What you wrote as ways to handle emotion "during trading" does not portray the traders trading but general parts of the dos and don'ts of traders even before trading. If it were to be during trading indeed, the only antidote is for the trader to take a break immediately. Such a trader can now continue to ponder what happened and how to deal with them in subsequent trading. But as a whole, I can deduce that you are referring to what traders can do to avoid emotions (before trading), and the only solutions I know are discipline and determination, nothing else. Discipline is always an anti-emotion anywhere, that's what I always preach that traders should possess.
While the determination to be disciplined should follow so that the will and the inner self will work together to fulfil the trader's desire on this subject. This simple psychology has ever been helpful and I only trade the time I want to and do exactly what I planned to do due to that.
On one hand, it may seem that it is impossible to take control over emotions while trading, but at the same time, everything is possible in trading in case of constant learning, seamless practice and pure desire to attain goals in the financial industry.
This is a very good statement, and like I always say, it is what you think you can't achieve that you will not achieve, but if you believe you can do it, you will do it. Emotion is psychological, which requires psychological solutions, but we need the determination to actualize it. That determination is what most traders lack. Once you possess that in addition to discipline, then your case is settled regarding emotion. But also, one must observe some good trading rules like investing the amount that one can afford to lose, trade the right time and for the right purposes, trade with the appropriate risks and management among others.