Illustrator Kakeru shared a drawing on Twitter showing what Broly from Dragon Ball Z would look like if he transformed into his Super Saiyan Blue state.
In Dragon Ball Super, the Super Saiyan Blue state can only be achieved by first evolving with Super Saiyan God, that power can be activated as Goku said: “One becomes a Super Saiyan God and then becomes a Super Saiyan again.”. Super Saiyan Blue is actually a Super Saiyan transformation with God Ki achieved in the Super Saiyan God state.
Unlike previously released Super Saiyan forms, in his Super Saiyan Blue state, Goku's hair turns blue rather than yellow, making it look more unusual.
Dragon Ball Super has not yet confirmed whether Broly achieved this transformation or not, there are those who do not believe it is possible. Because he has his own legendary form, which can be improved and has been proven to be stronger than Goku's Super Saiyan Blue.
Of course, there's nothing stopping Broly from being able to combine both of the above transformations and take it to the next level, elevating his legendary status, but for now that's still just a distant dream.
In addition to the above work, Kakeru has a lot of interesting Dragon Ball artwork on his profile, so if you like it, check out this person's profile to see more.