Lou Ferrigno appears in green skin as an Orion reminding us of his earlier Hulk days. He has many more lines in this than he ever spoke throughout the entire Hulk series.
Fiona Vroom has a cameo in Star Trek Beyond (2016). She can be seen as an Orion crew member during the "Captain's Log" scene.
Lou Ferrigno previously played the Hulk, and voiced the character in the first two Avengers films. On the original television series, the creatures growl were provided by Charles Napier, who also appeared on Star Trek (1966). In Hulk (2003), Bruce Banner is played by Eric Bana, who also appeared in Star Trek (2009).
Kirk appears to have trouble focusing while reading at the beginning of the episode. This is a subtle nod which alludes to his needing glasses to read, as shown in Star Trek II: The Wrath of Khan (1982).
The Saurian Brandy bottle, which appeared in several episodes of the original series, appears in this episode in the dinner for Zaminhon (two bottles on the table). The distinctive-shape bottle with red leather straps was actually a modified George Dickel 1964 commemorative edition "powder horn" whisky bottle.