Are you talking about 1H NMR? In the general case, it is not so easy to say - it depends on all substituents, with geminal substitution usually contributing most to change in chemical shift. trans and cis substitution will affect chemical shifts differently, but will depend on the electronegativities of all groups concerned.
For your example, there will be very little difference between chemical shift for these two methyl groups, but the methyl trans to the alkyl chain is probably slightly downfield shifted. Coupling constants for the two methyl groups would be slightly different. In acyclic systems, 4J couplings from a methyl to a cis or trans proton can range from about -3 to +2.5 (but usually 0.8 to 2), and usually |Jtrans|>|Jcis|. Of course, nOe information would also be useful.
If you are talking about 13C NMR, a methyl peak trans to a carbon chain will be downfield shifted from a methyl group trans to a proton.