Does this make sense? (Short TLT and TBT at the same time?)

Hello there,

I'm looking the formule for short selling bonds, or get some kind of cheap financing and after proving that i cant short sell US or Europe bonds (i'm from EU), i had the idea of short sell TLT and TBT (i can throught CFDs).

What are your thongs about this?

Looks like lowcost money borrowing way?

Thank you!