How to use substitute?

If I have “H” in the A1 I can get “H” converted to “V”
Or
If I have “V” in the A1 I can get “V” converted to “H”
By using following formula:
=SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(B3,"H","Z"),"V","H"),"Z","V")
if I have “H” or “V” in the A1 how can I get result = “T”
Thank you for help.