Yes, that is the tedious way of applying textures manually.  You can do it for one zone, right-click and select all, right-click and copy.  Go to each zone that shares the same textures, right-click and paste.  There are three major texture files to apply, torso, limbs and face (which includes mouth and teeth).  Avoid, using the apply to all parts, that will simply apply 1 texture to all the zones.

MATPose files and Material collections will apply the correct maps to all body part zones.  That is what they are designed for.