Something you don’t hear much about – Relics and Artifacts That Countries Are Still Fighting For: https://www.youtube.com/watch?v=Pr3VBm1CDTE (about 10:30 minutes long).
#11: Hoa Hakananai’a – https://en.wikipedia.org/wiki/Hoa_Hakananai%27a
#10 Nefertiti Bust https://en.wikipedia.org/wiki/Nefertiti_Bust
#09 The Rosetta Stone (not the language software) https://en.wikipedia.org/wiki/Rosetta_Stone
#08 Parthenon Marbles or Elgin Marbles: https://en.wikipedia.org/wiki/Elgin_Marbles
#07 Priam’s Treasure https://en.wikipedia.org/wiki/Priam%27s_Treasure
#06 Mona Lisa https://en.wikipedia.org/wiki/Mona_Lisa
#05 Sion Treasure or Kumluca treasure https://en.wikipedia.org/wiki/The_Sion_Treasure
#04 Euphronios Krater https://en.wikipedia.org/wiki/Euphronios_Krater
#03 African Artifacts Louvre: https://www.louvre.fr/en (official site English) looks like these will be returned: https://www.washingtonpost.com/outlook/2019/01/02/louvre-is-returning-sculptures-west-africa-heres-how-why-emmanuel-macron-made-it-happen/?noredirect=on&utm_term=.969dbb164c81
#02 Koh-i-Noor Diamond https://en.wikipedia.org/wiki/Koh-i-Noor
#01 Winged Victory of Samothrace https://en.wikipedia.org/wiki/Winged_Victory_of_Samothrace
I included Wikipedia links in case you aren’t familiar with some of the items.