How to set additional time frame for H2 (Two hour graph) and H8 (Eight hour graph) ?

 
Currently we have default time frame of M1, M5, M15, M30, H1, H4, D1, W1, and MN. Does anyone know how to set additional time frame for H2 (Two hour graph) and H8 (Eight hour graph) ?? Thank you
 

period converter

& BTW in "MT5" it's built in

Reason: