IRS Publication indicates that sole proprietors can deduct the cost of hiring a tax professional, such as a Certified Public Accountant (CPA), to prepare that part of your tax return relating to your business as a sole proprietor is deductible on Schedule C (Form 1040) or Schedule C-EZ (Form 1040).
See https://www.irs.gov/publications/p535#en_US_2018_publink1000209200
Note that there is no mention of deducting the cost of tax preparation software that is utilized by the sole proprietor to prepare Schedule C. However, it is probably reasonable to presume the deduction would be allowed. Regardless, considering the deductible amount has to be allocated to Schedule C alone (i.e., a fraction of the price of the software), it is most likely not worth entering.
