Or will I need to simply search up and then back down through every tree? I don't mind...but if there is a shortcut or work around...that would be great.
Short Answer: NO, not in "Family Tree" of 'FamilySearch', as far as I am aware.
Maybe, with one of the "Third Party" Applications, in "Sollutions Gallery" of 'FamilySearch', that is "Certified" to work with "Family Tree" of 'FamilySearch'.
Are you asking this question in relation to the results from DNA Testing?
well maybe not exactly what you were envisioning - but yes you can at least partially.
For example - if you go to you great grandfather in FS
and then go to the "View Tree" link
and then set it to "descendancy"
and set the generations to 4 - you will at least be able to see all your deceased cousins.