In the 1950s, Commonwealth decided to issue a couple of their silent Aesop Fables that they had as sound cartoons with a voiceover. According to this post  the shorts featured two types of voiceovers: 1. A male narrator with the characters voiced 2. A young boy and girl speaking over the cartoons as children enjoying the adventure along with viewers (dunno if these also had the characters voiced). So far, I have only found 3 shorts with the voiceovers (all of which are from the male narrator and none from the young boy and girl). They are:

The Picnic  (Retitle of In The Bag (1928))
Flying Ark  (Retitle of If Noah Lived Today (1924))
Dinner Time  (1928)

My question is, how many of these shorts were voiced over like this and how many of them are available?

I've never seen any of the "boy and girl" Commonwealth prints, either, but I'd wager they're essentially the same format as a few shorts that were in the syndicated "Mischief Makers" package comprised of the silent "Our Gang" comedies and shorts from a few other series, where there was an optional "boy and girl" track applied to the shorts in the package in which two children (named "Bobby and Bunny" in the opening credits for the package) would make comments throughout the film as it played, without the characters being voiced by another actor.

---

If you are looking for content to upload to your channel, you're gonna be out of luck as I've not seen that style of narration as of yet. Maybe eventually one print will circulate online, but if it comes from Tommy you of course know you're out of luck reuploading it. I unfortunately know little about which cartoons were apart of which styling of soundtrack Commonwealth did, but I know JOLLY ROUNDERS also had the general narration style and I'm dying to hear it someday