in userguide - lodermode that comes with animtools:
AUTOMATICALLY LOADED CHARACTER POSITION FILES
animtool position files may be automatically loaded when a character folder is loaded by placing a specially named position file in that character folder.
to do this, choose a position you wish to be loaded with a character, and rename the desired position to 'animtoolscharposition.txt'
then place this position file in the desired character folder.
after the animtools mod has been loaded, loading that character will apply the 'animtoolscharposition.txt' position.