Just my experience with the whole Legends thing. You can do the start season/association with legend teams make trades and export the team like mentioned. However there are some hang ups. Only the original home/away jerseys are carried over to the exported team. The exported team's warmups are all white no matter the team like during tip off or the players on the bench. No team records in association with exported team,
But the biggest killer is for people who wanted to take the exported team to an association. There is a glitch that doesnt let you trade or resign any of the players on the exported team even if 1 of the players was a current NBA player you cant trade or resign him. The CPU can sign them, but a clone is left in free agency of the player even if the CPU signs him. So using a exported team in Association is very much broken.
The other thing I noticed is if you load your exported team in the main menu then go to create a team and edit the exported team which makes it a regular created team with the same jerseys and logo options from previous 2k create a teams then take them to association you are able to trade the players. However again they will no longer have the original team logos and jerseys.
As for using Legends in Create a Legend mode I havent seen a way to do that. It only seems to allow current players from the current 30 NBA teams. You cant even create a player and put him on a team then select him he wont show up when selecting the player you want to use. However the create player is in creating a legend as a CPU player you just cant use him yourself. When selecting a player for the mode again it only shows current players on the current NBA teams no exported teams or legend teams.
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