You can’t disable the internal effect - the internal effects of articulations are those that change the duration (e.g. for staccato) and dynamics (e.g. for accent) - but you can edit them in Playback Options and in the Playback Options Overrides in the expression map. However, internal effects don’t make a difference to how the expression map is used to choose a patch/switch, and the playback technique area in your screenshot looks correct - I don’t think you should get “arco” playback. Can you attach a project in which this goes wrong, rather than a doricolib file?
(I don’t think Mutual Exclusion Groups are relevant here.)