(Not totally original, inspired from other quirks, but mostly my own ideas)
Quirk Name: Chaos Anomaly
Powers: I can reshape my body and body parts into whatever I want and I can choose the material of the shape. I can change my whole body into another person's if I wanted. I can speed up my own time or set it back. I can control the elements. I have zero range telekinetic abilities (E.g. I can effectively fly and put up invisible shields around my body. I can also drastically increase physical abilities at will. Enhanced overall abilities and healing.
Downsides: I revert back to normal when sleeping or unconscious. I sustain the damage from extra limbs or what I make even after I go back to normal. I can't change any else's time (Yet, can come from extreme training). Can lose control of my powers easily. Can easily be possessed. Needs to eat a lot and sleep a lot to be able to use powers. When I overuse physical enhancement abilities I can injure myself badly
Special Abilities: (Special moves using quirk) I can age rapidly or set my body back in time. OVERBLOW- I can use all of my abilities at once and at 100% making me effectively invincible (At the time) downside is that I can only us the ability once every 24 hours and feel extremely tired after using it.
ELEMENTAL BARRAGE- I use all the elements at once to create an apocalyptic super attack.
SHIELD PROJECTION- I project the shields around my body to create bigger shields wherever I want, the downside being for every 5 metres I project the shields being another 5 minutes I can't move.
TIMESHIFT- I shift time drastically. Maximum being 1 year back in time or 1 year forward in time. Downside is that I can only use it once every month.
Bio: I was subjected to human experimentation to be able to use a lot of abilities and not die while using them. One day a mysterious person came to the lab and set me free when no-one was looking and I rampaged and destroyed the lab while freeing everyone with the mysterious stranger. She helped us reintegrate into society and we eventually found out she was the leading scientist from the lab, but she disapproved of the torturous methods and freed us. I have since became a superhero and am still saving lives.
P.S You can make a super OP one but make some reasonable ones too