If the Robo-Advisors were just working within the ROTH account, then the cheapest "Free" version would work....but using the Free version would then depend on what else you did during the year to earn $$.
IF the Robo-advisors were working in a normal taxable account, and any sales transactions occurred, then the minimum software you could use is the Premier version in the "Online" software........(or any version of the "Desktop" software used on a full MAC or Windows computer...though Deluxe should be the minimum used there)