Without taking cost assistance into account, you’ll never pay more for a specific plan in a specific region regardless of how you shop. Prices are tightly regulated and prices of plans cannot be changed based on factors like commissions. In fact broker and agent commissions are paid for directly by the insurer out of a pool. If you go direct to an insurer, the insurer just keeps the commission.
The only things that affect the price of your health plan are: what plan you get, your location, your age, your family size, your income (if you are eligible for cost assistance subsidies), and factors like employer contributions. Your health or where you shop won’t affect the price of a specific plan.
FACT: You will never pay more for the same plan in the same region, before cost assistance, regardless of where you get it from.