Here's some brief ideas I've been working on for quirks, still haven't decided which one I'm going to use yet though...

Open Sesame: User can create two portals at a time. Stepping into one portal will instantly shift them to the other portal opened. The user can only open portals in his line of sight. User can open one portal, and store anything that is put into it for a limited period of time, he cannot open a separate portal to store more things inside if he's already storing something in one portal. He can only open a second portal to release what's inside, and regain his full abilities. 

Can't See Me: User possesses a third eye that is always open. When the third eye looks at a person, that person will be unable to notice that the user exists, but only while the person is in the user's line of sight. It's prone to dry eye, and is particularly susceptible to dust. Obviously the user has to keep the eye covered when out of combat so he can be seen by everyone. 

Hungry Hands: User possesses a mutant quirk that created a large mouth on each of their palms. The mouths can eat through anything, regardless of what it is. Whatever the mouths ingest, the user can turn into or expel out of their bodies for a period of time. So for example, if the mouths ate a metal pipe, the user would be able to turn their bodies into metal. If the hands ate an open flame, the user would be able to light their bodies on fire or spew it from any of their three mouths. 

Friction Force: The User can increase or decrease friction upon themselves and anything they touch. This ability allows them to increase their mobility by reducing the friction on their feet, allowing them to "slide" around. They can also move on walls and through difficult places by increasing the friction on their feet or hands. Another application of this quirk is enhanced combat and immobilization capabilities by either increasing or decreasing friction of themselves or their opponents. 

Polaris: The user has the ability to attract or repel things with his limbs. His left arm and right leg can repel things while his right arm and left leg can attract things. The user can't use the same ability consecutively, so if they were to use the attract ability, they would have to use the repel ability next. The users fighting style revolves around his mobility and ability-enhanced strikes.