As WikiTree does not auto-load names from a GEDCOM file as other sites do, no.
When you run the GEDCOMpare, any of your Existing Profiles will show up as a Suggested Match. Accept the Match, but you do not have to Merge the data again to that Profile. This is one of the few times I suggest you use the Completed Check Box in the first column to let the GEDCOMpare Process know you don't plan on doing anything with this name.
If there is new data in this GEDCOM file for one of your Profiles, it is better if you manually add this updated data manually to the Existing Profile than use the Merge function.
Also, be aware that if there are more Suggested Matches to a name in your file than just your Existing Profile, you will still need to Reject or Accept those Matches to later Add any new names to WikiTree. If you get another Suggested Match besides your Existing Profile that closely or exactly Matches your Existing Profile, this more than likely is a clue to a Duplicate Profile of your Existing Profile and the two Profiles may need to be Merged.