Those four games are Balloon Bomber, G-Darius, RayStorm, and Syvalion which were also the four exclusive games on the Playstation 2 version of Taito Legends 2. There are only four games included that aren't available in the Xbox/PS2 versions of Taito Legends and the Xbox version of Taito Legends 2. The sole exception is Taito Memories Gekan. The Taito Memories lineup for the PS2 has many games we never got in the Western compilations. You almost have to get all of these to have the best experience. And Bubble Symphony saw a Japanese port on the Saturn back in the day, is on the PC version of Taito Legends 2, was included on the region free Taito Legends 2 for the Xbox in Europe, and was included on Taito Memories II Gekan in Japan for the PS2. And as far as I know, Taito Memories II Joukan has the only home version of Bubble Memories. Below are the game lineups for the PS2 Taito Memories line. It isn't hard to find that information using a search engine. And the PSP saw a single Taito Memories release in Japan and a single Taito Legends release in the West.

And Japan got 4 Taito Memories releases for the PS2 (The content of one volume is available between Taito Legends and the PS2 version of Taito Legends 2, but the other three all have exclusive games).

The Xbox and PS2 builds for the sequel each had 4 platform exclusive games not available on the other. The PS2 and Xbox builds of the first Taito Legends share the same game lineup. There are two Taito Legends releases for North American/Western consoles.

Taito legends 2 rom