Playing on PS5. Video attached. Had to test it a few times to be sure. When placing tools in a chest on land. Then going to the underwater farm and find tools there "copies" them to your inventory. The ones in the chest remain. Can't delete or sell the duplicates. The ones already there were tested over 3 in-game days. It started with the lumina wand.
#Duplicate tools
placid sun
shadow lion
Hello @placid sun I'll relay all the information you have provided to the team for checking and I'll reach back to you if there's any additional questions 
Thank you so much!
placid sun
Thanks! Will answer any question I can. 
placid sun
Just to confirm, I tried again and it's only the first duplicate so a second duplicate doesn't happen, only the first
shadow lion
Just to confirm, I tried again and it's only the first duplicate so a second dup...
Thank you for your update! I'll relay the additional information to the team for further review