I realize the title is vague, so I hope to clarify the situation to the best of my ability bellow in order for readers to come up with a well-developed stance on the fight, which will not take place in Minecraft.

According to the Minecraft wiki, "Herobrine is able to build and destroy in Minecraft. The original image states the player found long 2×2 tunnels, small pyramids in the middle of the ocean and trees with no leaves. The full extent of Herobrine's building capacity is unknown, but the given examples indicate Herobrine has awareness of shape, and can differentiate materials from each other."

However, it also states " It is unknown if Herobrine can swim, use minecarts, boats or Nether portals. Like most ghosts, it is likely he simply has no use for most methods of transportation."

How can he destroy/create things if he is a ghost? For the sake of consistency, let's say he is a ghost that can simply break blocks, despite it going against usual ghost conventions.

Regardless, George, Mary and Rebecca can have as much as a year of prep time if needed. Essentially, Herobrine will be plopped in front of them, without any further info, while G, M and R can prepare for his arrival for a whole year.

In my opinion, despite their age, I think that G, M and R would handily take the fight simply with their prep time and home field advantage. What do you guys think? You may have strong opinions, but please keep the discussion civil!

You may ask for further clarification, and I will try my best to answer your questions.