First, I have to admit that I am a left-hander. This is partly a personal account.
Lefthanders often have an advantage in sports. In Baseball, Tennis, Soccer, this advantage is obvious.
But do left-handed chess players have an advantage in chess?
Let’s take a general, and perhaps an overgeneralized view, of left-handers.
Lefties tend to think spatial setups rather than individual items. They see multiple colors in everything rather than in White and Black and iron clad differences. They tend to do better in geometry rather than algebra. They see forests rather than the trees.
And they tend to see the whole board patterns than rather than the calculations.
Does this constitute an advantage? Well, yes and no. It more or less balances out. You have to see more than a corner of the board and you have to calculate.
Are there other things that may constitute an advantage for a lefty?
Let’s use this image of two players in a tournament with a clock. The tournament is from 1944.

As you can see both players can access the clock, but there is a difference. One player punches the clock with his right hand and the other player must use his left hand.
Most players naturally want to have the clock on the side of their dominant hand. So, who gets to choose which side of the board the clock sits during the game?
Since White gets to move first, Black has a small compensation awarded to him. He has the choice which side to place the clock. So, if I am playing Black, I will choose the clock on my left-side and tell my opponent I am doing a him a favor, “just to be nice”. In reality, the position of the clock now favors both players.
And when I am White, I freely and liberally let Black to place the clock to whatever side he wants. First of all, it is a chess rule. The second reason is that the clock almost always ends up on the side I want.
Except when my opponent is another lefty.