How does he suffix- less affects the meaning of expressionless and fearless?

It affects the meaning of some words (such as the ones you have stated) because it tells that there is without someone or something.

The details about the statues, i believe, are that they're carved from blocks of igneous stone, many of them are partially buried under the ground which to preserve and protect them from the harsh environment on easter island, and many of the facial features have washed away. also, the most well-preserved one is at the british museum in london.these are just guesses from what i can see and what i think i read correctly. i'm sorry i couldn't be more .