Are these metamers, if not why?
The term metamer isn't terminology that is widely used today, and indeed doesn't appear in the IUPAC Gold Book (the International Union of Pure and Applied Chemistry publishes guidelines for standardised nomenclature in chemistry and is widely adopted). 

The description you're looking for is structural isomerism, with the compounds you show being examples of positional isomers (isomers which differ by the position of the functional groups, for instance in this case the relative positions of the methyl and methoxy moieties).