I presume you are referring to a formula that starts with "=+" instead just "=", for example:
=+A1+B1
It has no meaning. The "+" after "=" is superfluous.
It is a carryover from Lotus 1-2-3, where formulas can be entered as +123+456 instead of =123+456. Excel permits that form as well. It changes the first to the latter.
In any case, there is no reason to use the +A1+B1 or =+A1+B1 convention.
If you are trying to tidy up the work sheet then you could do this, use find if you have many and change them one at a time if you did a find and replace all, you could remove the + from with in a formula and that would be a disaster, good in a movie but not so good in a spreadsheet..... .......But I know you will do a backup before you do this....just incase.