If you are using PC version of the game. You could try using fusion chao editor which can be downloaded from here:
https://chao.tehfusion.co.uk/chao-editor/
Alternatively, you could try using my importer/exporter which lets you do the same thing
https://gamebanana.com/tools/6742
You can simply download the program of your choice and enter chao garden, then find chao name in the program and click on that name, and press export it. Then log into other game(that is sa2b, you have to be in chao lobby) and choose a slot of your choice and press import. Then your chao should appear in other game.
These programs are useful cause basically you can save chao into small file (.chao) which can be transported from one game to another, and even share it among people if you wish
If you will be using Chao importer/exporter, you can find tutorial here:https://gamebanana.com/tuts/13166
P.S: to avoid any problems, I strongly advise you to run the programs as administrator, otherwise they might not export/import and some functions might not work