Due to the Nature of their creation these creatures developed with poor eyesight mainly relying on their other senses to hunt.

Notably, xenomorphs will alter their physical appearance during development depending on the physiology of the host in which they gestate. Likely, this incorporation of physical traits gleaned from the host is designed to ensure the adult creature is better suited to the environment in which it will find itself. Historically, most xenomorphs encountered have typically gestated inside human hosts, and therefore adopt a basically bipedal, humanoid stance. Increase your Constitution by 2 and your Dexterity by 1

The actual age of a xenomorph is unknown

Xenomorph adults can stand from 5 to 8 feet tall and average 300 pounds. Your size is medium.

Your base walking speed is 35 feet

You are a race bred for combat. You have three natural weapons which you can use to make unarmed strike that you are proficient in

 Your exoskeleton, though bipedal, is not the regular shape or build of other humanoids. Armor must be created for you and costs twice as much as a regular suit of armor. You have a natural Armor Class equal to: 12 + your Constitution modifier.

Your exoskeleton, though it is tough, it is not invulnerable, you are vulnerable to fire damage. In addition you have disadvantage on saving throws against extreme heat, detailed in chapter 5 of the DMG.

You are Immune to acid damage. Additionally, when you are damaged by a melee attack, you may use your reaction to coat the creature in caustic blood. The affected creature must make a DC 8 + your proficiency bonus + your Constitution modifier, Dexterity saving throw or take half of 2d6 acid damage. This effect increases in damage by 1d6 when you reach 5th level(3d6), 11th level(4d6), and 17th level(5d6). You regain use of this trait after you finish a  long rest. 

gain proficiency in stealth and acrobatics

You can telepathically speak to any creature you can see within 30 feet of you. You don’t need to share a language with the creature for it to understand your telepathy, but it must be able to understand at least one language. This process of communication is slow and limited, allowing you to transmit and receive only simple ideas and straightforward concepts.

Xenomorphs understand common but, cannot speak themselves