For Yuri's Bohdi Blastia, can I assume that it gives him the enahnced strength and abilities as it does in his world or it would just be a decoration piece?

from the wiki here are its abilities:

Bodhi Blastia: is small blastia commonly crafted into bracelets and necklaces to be worn as accessories by the user. They are sometimes embedded into equipment such as Karol Capel's bag, and used to amplify the wearer's abilities for increased strength.