The original data structure was just 44 bytes, and did not have space to store met data or the type of Poke Ball you caught it in. The G2 structure ups that to 48 bytes, and Crystal specifically, as opposed to G/S, started tracking "met area" and "met level" (as well as "met time of day", a little feature that forced them to compress down the "met level" segment to make it incapable of storing levels higher than 63, which is probably a big reason you encounter level-60 legendaries in that game as opposed to level 70). Those bytes are unused (but still reserved) in the G/S structure, so anything you catch in those games will have blank data there, but you can trade Pokemon from Crystal to Silver, then trade it back, and the bytes are still there so you can look up the met data again. Still, none of those games used the extra bytes to store Poke Ball type either.
Because there's no record of this data, if you're moving a Pokemon from the VC Game Boy games into Pokemon Bank, everything will automatically be placed in a regular Poke Ball as part of the process of equipping it with a modern data structure.
