When Dead or Alive 5: Last Round was released back in March, it lacked any online functionality. Tecmo KOEI and Team Ninja aimed to release a patch that would enable this mode in June, however after a beta phase, the development team decided to further delay it.
As Team Ninja noted:
“We are currently beta testing the update to add online functionality to DEAD OR ALIVE 5 Last Round on Steam. We originally announced that we would release the update by the end of June 2015. However, due to major issues found during the beta test, we will be postponing the release of the update.”
Currently there is no ETA for this patch that will enable online functionality to Dead or Alive 5: Last Round.
Team Ninja is still offering a beta version that features online functionality, and for which all owners of the game can opt in.
In the library, right click Dead or Alive 5 Last Round and select Properties. The, select the BETAS tab, and select the beta you would like to opt in. If you’re experiencing performance or stability issues, Team Ninja recommends opting out by selecting “NONE” in the BETAS tab.