Yes indeed. The current magnetic heading will be 88 degrees, and that is what you would read on your heading indicator if flying this airway in a zero wind situation. MSFS does have the current 2020 world magnetic variation map embedded into the default scenery, so this should be correct when flying in the sim.
I got my PPL in 1988, and at that time, students were taught to plot cross country flights using a sectional chart and a plotter. I presume this is still done today. A plotter is combination of a calibrated ruler and a protractor. The ruler is graduated in nautical and statute miles, specifically for use with sectional charts. The protractor is used to measure the angle between the meridians of longitude printed on the chart (which are aligned to true north), and a course line drawn on the chart in pencil during flight planning. You then add or subtract current magnetic variation to the true course to get the magnetic course that you will use while flying the course.
Many persons looking at sectional charts mistakenly assume that the zero degree north radial of the compass rose surrounding a VOR points at current magnetic north, but that is not the case - it points at where magnetic north was when the VOR was last calibrated.
In the case of my previous post with the screen capture of the sectional chart showing EHK, if you were to use the paper sectional and a plotter and extended the zero degree radial so that is crosses the adjacent 113 degree meridian of longitude (which runs true north and south), then measured the angle between the two, you would find the angle is 16 degrees - the 1965 variation.