It works like that in French until you use a different word for the machine.

"Mon ordinateur est une bonne machine". In a single sentence my computer was described with words both male and female.

It's just vocabulary and grammar, not the deep essence or identity of things or people.

I didn't learn of any rhyme or reason to it in German when I took classes on it. In fact, in a few cases, the gender changes the meaning of the word. Der See und die See, for example. One means lake and the other means sea/ocean.

it is in German too.

It is die Waschmaschine. and a Steam Engine ist die Dampfmaschine. And it is a very straight foreard naming convention. Just add what kind of machine it is to the front of the noun.

i don't recall there being any rhyme or reason to gender in german, but it's been many years since i studied. i do remember that the gender of any word like ____-machine would be whatever the gender is for machine.

The general rule of thumb in French is the word is feminine if it ends with "-le" like "la table", the table is feminine with it the article "la" to denote feminine. But this is not always the case. For example, house in French is "la maison" which doesn't end in "-le".