Testosterone does make men more aggressive

Feeling aggression is as emotional as getting upset about something/feeling like crying.

but it also lowers empathy and can make it difficult to read emotions Having less empathy doesn't necessarily mean having less emotion in general. Just having emotions about different things. Like getting pissed off about stuff often.

There is some anecdotal testimony from FtM trans where they find that they become less emotional and have a harder time connecting with others.

Yes, key word being anecdotal and as long as we're talking about personal experiences, I really think that people who say that kind of stuff are probably experiencing a placebo effect more than anything else. They think ahead of time "oh, men are less emotional and stuff" and then they take a pill that they think will make them feel more like a man... and presto, they suddenly "feel less emotional".

Also someone doing FtM isn't a male biologically so there is a chance that even if the testosterone really is making them feel less emotional, they still aren't a male who has natural testosterone and is made to naturally have lots of testosterone so they might not be experiencing testosterone the same anyway. I'm not trying to disrespect trans people--I just don't think you can use that as proof of how testosterone works in biological males.

Also I'm not really saying women are or are not less emotional than men (I don't they are), but "The more estrogen in the body, the more emotional the person becomes. The more testosterone in the body, the less" just isn't scientifically accurate.