modifying exponentials using a rule

Questions
1

For an expression like

E^(I x Subscript[p1, m] - I x Subscript[p1, \[Mu]] - 
 I x Subscript[p2, m] - I x Subscript[p2, \[Mu]])

how does one go about substituing E^(x*Subscript[p1, m]) with E^(Subscript[\[Omega], Subscript[p1, m]] t - Subscript[p1, m] r), and continute to substitue (with explicitly replacing each string), so that E^(-I x Subscript[p1, \[Mu]])would be replaced by E^(-r Subscript[p1, \[Mu]] + t Subscript[\[Omega], Subscript[p1, \[Mu]]]) and so on?

2

Is this perhaps what you are looking for?

In[1]:= E^(I x Subscript[p1, m]-I x Subscript[p1, \[Mu]]-I x Subscript[p2, m]-I x Subscript[p2, \[Mu]]) /. 
 x*Subscript[symbol1_,symbol2_]->Subscript[\[Omega],Subscript[symbol1,symbol2]]t-Subscript[symbol1,symbol2]r

Out[1]= E^(
 I (-r Subscript[p1, m] + t Subscript[\[Omega], Subscript[p1, m]]) - 
 I (-r Subscript[p1, \[Mu]] + t Subscript[\[Omega], Subscript[p1, \[Mu]]]) - 
 I (-r Subscript[p2, m] + t Subscript[\[Omega], Subscript[p2, m]]) - 
 I (-r Subscript[p2, \[Mu]] + t Subscript[\[Omega], Subscript[p2, \[Mu]]]))
3

Yes Bill, that’s it.
I have no idea why my browser can’t render the Mathematica display (firefox and chrome).