1)It is a common thing for most of the time to represent a person whose gender is not knows as masculine.

2) Each person represents himself is correct according to grammar.

Reflexive pronoun is always used when the subject itself is the doer of the object. There are a few verbs like Bath hide and more where reflexive pronoun is not used. It is because it is well understood that if you will bath then it would be by yourself ( in general). Sometimes, it is used to put emphasis on the subject.


The children cooked the dinner themselves. Here, we are trying to show that even though they are children, they have cooked the food on their own without any help.

Personally if I wanted to me sure of being gender neutral in a sentence like that I'd go with something like.

[i]Each person represents themselves through their way to address others and their behaviours.[/i]

You are way ahead of me...and I was born speaking English...