In this interview, Martin states that he uses a plug-in called Little AlterBoy. He highly praise’s it’s formant shifting feature. Martin mentions using the Alterboy at 24:35 in the making of Ocean.

In a Heavy Mellow Instagram livestream on July 25, 2020, Skrillex is seen using the Soundtoys Little Alterboy plugin at the 07:20 mark.

In the YouTube video titled "Paul Meany - Twenty One Pilots - Next Semester - Production Peek" Paul Meany discusses Tyler Joseph's use of the Soundtoys Little Alterboy plugin at the 0:52 mark.

At 33:18 , During his interview on Pensado's place, he mentions he uses Little Alterboy, among many other plugins, in his productions.

At 6:10, they explain how they used to make a vocal layer for the lead in the break.

At 2:20 you can see he is using the litle alterboy for his vocal chops.

Used for Albarn's vocals on Gorillaz's "Charger", as mentioned by recording engineer and frequent collaborator Stephen Sedgwick in this July 2017 Sound on Sound interview about the production of Humanz.

“The vocals start at track 42, with Damon’s lead vocal. The main lo-fi telephone-like effect is the typical 2-D sound, because this is a 2-D song. I can’t tell you what it is, but it’s done with hardware. The plug-ins on the inserts are a Waves Renaissance De-esser and RVox, and the Waves Kramer PIE [compressor], which I use a lot on vocals. Below are two tracks of lead vocals with delays.

While recording, I often use the SoundToys EchoBoy for delays, but I replace that with hardware delays to get more character. In this case these two tracks are prints of me running Damon’s vocals through a Roland SDE 2000. I was having fun with that, doing fast delays and delays with modulation. Then there are some Damon harmonies, and the yellow tracks are him singing the chorus, and some of these are pitched down an octave with the Little AlterBoy. I usually compress vocals with outboard, either using Empirical Labs Distressors or sometimes the Summit TLA 100A or Tube-Tech CL1B compressor. If want to impose a lot of character I’ll engage an old Collins broadcast limiter. For reverbs on the vocals I often use the studio’s EMT 140 plate.

“Six of the saxes tracks have the Little Altar Boy. That is such an interesting and creative tool for changing the formant, and it has pitch shift capabilities up to 1 octave above or below the original. You can change the masculinity of how something sounds, and those saxophones are very dark, and they come in and build right before the drop, and by turning the formant down with that plug-in I created something that almost sounds like saturation, but that makes it a little bit tougher sounding"

in this post the vst can be seen

at 4:16 Mark in the video you can see the little altar boy plug-in clearly on the screen

In a livestream titled "4.5.20 - Quick CoronaJam!" on Shinoda Livestreams, Mike Shinoda demonstrates his use of the Soundtoys Little Alterboy plugin.

Top left corner of video at 2:01:14 shows him opening (and demonstrating) the software

From 2:01:42 to 2:01:58, Jacob says, "It's fun, isn't it?" and "It's nice for that kind of high impact bass voice(s)"