Yes. Japan places no general restriction on foreign individuals or companies owning real estate, and hotel condominium units are bought and registered the same way as other property. You do not need a visa or Japanese residency to own a unit.
What you need
Buyers usually need a way to send the purchase money to Japan, a signature certificate or notarised affidavit in place of a registered seal (印鑑), and a judicial scrivener (司法書士) to register the transfer. The broker explains the important matters (重要事項説明) before the contract, and you sign the hotel lease and asset management agreements at the same time.
Rent and tax for non-residents
If you live outside Japan, rent from the hotel is generally paid after Japanese tax is withheld, and you may need a tax representative (納税管理人) to file a return. Our guide on how rental income is paid and taxed covers this in detail. Ask a tax adviser about your own country's rules as well.
Memberships are different
Resort membership clubs set their own admission rules, and some require a Japanese address or a member's referral. Check the club's conditions before you bid on a membership.