A man dies and get reincarnated in MCU with the power of mind. The powers related to mind are based on the movie 'Lucy'. How much power MC get is upto author. The MC is not born as any of the hero or villain but as a simple boy in a middle class family. He is born some 15-20 years before the event of Captain Marvel (whayever the age author want him to b at that time).
As he has at least photogenic memory, he has studied a lot after being born and has developed a similar serum to that of developed by parents of Spider-Man (something like adaptability serum). He also has built machine to transfer the power from a source to himself.
He use machine first on the seed left by Ego (father of star lord) on Earth then on tesseract during the events of Captain Marvel. Of course from infinity stome he can't just suck all the power only enough to gain some power to himself. From there he start mastering the power gained by these sources.
Power from Seed can b energy manipulation and from tesseract (space stone) it can be like instant transmission (from the anime series of Dragon Ball Z).
From the mind stone the power can b mind reading nd protection of his mind (not mind control, that would b too OP if mastered fully and properly just think if prof X has more power over mind, thanos comes and prof X takes control of his mind.... end of the plot :p).
From Power stone the power can be increase in power in any factor according to author just not too much like one puch and thanos is destroyed or someone of same power level.
From reality stone the power can be the power of illusions (here author has to be real imaginative as this power can really help mc) without becoming reality as i think reality stone has the power to do that and not just over powered illusion.
From time stone he can get the power of time skip (power of Hit from anime Dragon Ball Z). The time duration of time skip is also upto the author just not too long that he again become too OP.
From Soul Stone he get understanding of all kind of souls and thier physiology. But with the help of energy manipulation gained from the seed of ego, MC can become a Healer. If author wants to change power gained by soul stone he/she can do it.
To get soul stone MC can use the help of power stone and reality stone. As I think the tesseract sent Red Skull to soul stone when he was loosing from Captain America. There he get some of the power of soul stone and was able to learn some information of anyone by contacting their relatives soul (like name of father of Natasha from soul of her father himself). And gives the soul stone by manipulating the visitors to kill other and using the soul of dead one to empower himself. So with the help of power stone and reality stone MC might b able to manipulate and overpower the Red Skull and get soul stone.
Author can use the MC mind powers to build a spaceship for him or can use instant transmission to travel to other locations of stones. Of course for time stone MC have to get it from Ancient One and for that he can start gaining her trust by offering her help as a healer. Try to get the power of time stone last as it is really OP skill.
As i have only told just the power of photogenic powers from 'Lucy' movie Author can also take other power from that movie according to his/her idea to continue the story.
Author can use either only MCU or other marvel comics too. Author can also continue it for the fourth phase of MCU. Really hope someone good take this idea and write a good fanfic.
Anyone who start writing according to this idea please inbox me the link or at least leave the link in comments section.