2
It's an interesting competition , both are amazingly powerful , Strange's magic skills are improve a lot since his first film and he can even fight almost equally with Thanos who already have 4 stones in the lastest film but Hela , on the other hand she's one of the fiercest fighter we've ever seen in MCU with immense strength and skills , her ability to call unlimited weapon is very dangerous and personally I think Hela have a centuries experience in the battle so she could held her own against Strange , it's possible she will be a winner but Strange will make a good fight.