What happens if you block another player?

I've experienced both situations.

When you block a player, their name gets replaced with the label, "Reported Player."

When I was blocked, I was an officer. I think that the group members in question were trying to prevent me from kicking them out of the group. However, I still could remove them from the group, by the way, because the buttons were still available to me on the dashboard. What alerted me to the fact that I got blocked was that their names disappeared from the top section of the boat list (the "You Gifted" "Gifted You" section), and that I could no longer give them a bush. I could still read their in-game names on the roster, but that might have been because I was an officer at that time.

As a person who placed a block on someone else, a similar thing happened. The person's name disappeared quickly from the top section of the boat list, but I'm not sure what happened on their end. I assume that my name disappeared from the top portion of the list. However, I could still see their presence on the bottom part of the boat list (under the "More Friends" section) although their name was now labelled as "Reported Player." Their name would eventually drop off the list after 20 (?) days or so. I did not try to give them a bush in this situation, because I wanted to cut ties with that person, especially since that person eventually left the group I was in.

In the chat, the blocked player's messages still appeared in the chat, but instead of their name, it read, "Reported Player. Message hidden."

If the block is successful, the other person shouldn't be able to give you a bush, and you shouldn't be able to see the content of their messages, although you might still be aware that the writer of the message is that person.

Once you block a person in Facebook, they will not see you, and you will not see them in any FB forum or in the game.

I'm the writer of the answer just submitted minutes ago...just a couple of more thoughts.

I described what I saw in the chat in reference to messages that had previously appeared in the chat before I placed the block on that person. I don't know if I would have been able to see later messages posted by that person after the block was placed.