Microfiber materials are not good sources of clothing. The fabric raises the body temperature and causes you to sweat excessively. To prevent chafing or other issues you will have to wear other clothing inside of the onesie and that includes socks. Preferably cotton to absorb the excessive wetness.
Maybe a mix of materials would provide the same softness with a breathable and comfortable wearing experience like the bathrobes, which are absolutely lovely (possibly because they're open and air gets in).

If you can get beyond this detail, it is very soft and comfy.
Just my honest opinion

An added comment and lowered star *constantly shedding the material. It's all over everything! Even after washing. SMH won't purchase again or recommend