Warning: SPOILERS for Star Trek: Strange New Worlds' Season 1 Finale - "A Quality of Mercy"
After his voice cameo in Captain James T. Kirk (Paul Wesley). As such, there were new personnel on the Enterprise in this future, which includes Chief Engineer Montgomery Scott.
Pike's Enterprise needs a new Chief Engineer after Hemmer (Bruce Horak) died in Strange New Worlds episode 9. Hemmer came aboard the Enterprise at the end of Strange New Worlds' premiere to Pike's new five-year mission. The blind Aenar quickly became the mentor of Cadet Nyota Uhura (Celia Rose Gooding) and her education from Hemmer included much more than just learning how Engineering operates. Uhura is a damaged soul who didn't feel she truly belonged in Starfleet. Hemmer counseled Uhura to make permanent bonds with her friends on the Enterprise, and the Aenar proved his own words when Hemmer sacrificed his life to save his crewmates from the Gorn. Hemmer's noble death leaves a void on the Enterprise as well as the critical role of Chief Engineer that has yet to be filled in Strange New Worlds' season 1 finale.
Scotty was only heard and not seen in Strange New Worlds' finale but the familiar Scottish accent and his claim to Spock (Ethan Peck) that he's "not a miracle worker" was unmistakably Mr. Scott's. It makes sense that Scotty is the Enterprise's Chief Engineer during Pike's version of "Balance of Terror" since he also had that post on Kirk's Enterprise in TOS. The question is whether Scotty will actually Strange New Worlds in season 2 to succeed Hemmer as Chief Engineer. Star Trek canon is vague about Scotty's Starfleet record before he ed Kirk's Enterprise so there's leeway for Mr. Scott to come aboard Pike's ship and simply remain at his post when Kirk takes over. However, it's also possible Strange New Worlds will introduce a new Engineer and save Scotty's debut for the future.
What Scotty's Voice Cameo Means For Other Enterprise Characters
Strange New Worlds' willingness to incorporate other Star Trek legacy characters and position them for their eventual roles aboard Captain Kirk's Enterprise bodes well for future cameos. Now that Scotty has been acknowledged, the three remaining icons from Kirk's Enterprise yet to be seen in Strange New Worlds are Dr. Leonard McCoy, Hikaru Sulu, and Pavel Chekov. Curiously, McCoy was never referenced in Strange New Worlds' finale, even though it's reasonable to assume Bones was Captain Kirk's Chief Medical Officer on the USS Farragut. Chekov is the youngest of Kirk's crew and he may not even be in Starfleet Academy yet during Strange New Worlds' era circa 2259. As for Sulu, he could already be in Starfleet but Pike's Enterprise currently has an excellent helmsman in Lt. Erica Ortegas (Melissa Navia).
There is certainly no lack of Star Trek legacy characters already in Strange New Worlds. The prequel has done a phenomenal job of featuring Captain Pike, developing Number One AKA Lt. Commander Una Chin-Riley's (Rebecca Romijn) backstory, giving Uhura more agency than TOS ever did, exploring the doomed relationship between Spock and T'Pring (Gia Sandhu), and deepening the characters of Nurse Christine Chapel (Jess Bush) and Dr. M'Benga (Babs Olusanmokun). Lt. La'an Noonien Singh (Christina Chong) also has a compelling blood relationship with Khan (Ricardo Montalban). There's no indication thus far that Scotty will Star Trek: Strange New Worlds season 2 or who would be cast as the Scotch-loving Engineer, but his place on the Starship Enterprise is canonically assured nonetheless.
Star Trek: Strange New Worlds Season 2 premieres in 2023 on Paramount+.