No. Pokemon Blue was for the GameBoy while Pokemon Ruby was for the GameBoyAdvance. The games are not cross compatible.
No.
do u mean Pokemon blue or do you mean SAPPHIRE You trade to SAPPHIRE the normal way but u cant trade to blue
you can not trade crystel with ruby because Pokemon cristel is a different generaion than Pokemon rudy
No.
No
Any Pokemon you want to trade to the other game
Yes after becoming Pokemon champion in both games you can trade but after firered delivers the ruby and sapphire to celio at one island then you can trade.
Pokemon blue to ruby is sapphire.
You can trade from Pokemon Ruby to another Pokemon Ruby using a link cable.
Red, Blue, Yellow, Gold, Silver, and Crystal can trade between themselves. Ruby, Sapphire, Emerald, Firered, and Leafgreen can trade between themselves. Games from list 1 cannot connect with list 2.
I'm going to assume you mean "Pokemon Ruby" in your question. Anyway, to trade between Ruby and XD, you must beat Pokemon XD and defeat the champion in Ruby.
i don't think you can you can only trade from another firered, leafgreen, or a ruby, saphire, or emerald game