Yes, an accountable expense reimbursement plan has always been useful for employee reimbursements, because even before TCJA unreimbursed employee biz expenses on Sch A were not a help to non-itemizers or to those where AGI limited their other credits/deductions and no help for most states. After TCJA, it's about the only way for an employee/owner of an S- or C-corp to be made whole. The corp gets to deduct reimbursements made to employees per their plan; the employees do NOT have added income. Been using accountable plans for my clients since decades ago at HRB.
A snippet from TTB: "Author’s Comment: An S corporation with an accountable plan in place can reimburse shareholder employees for authorized expenses. Under a properly structured plan, the reimbursements will be deductible for the corporation and excluded from the shareholder employee’s income. See Accountable/Nonaccountable Plans, page 8-11, 1040 Edition/Deluxe Edition."