Marking the opportunity to renegotiate Annex C of Itaipu Treaty for 2023 as a milestone for Paraguay, various ideas emerge for the country's development. One of them is the commercialization of energy to neighboring countries. To achieve this, it is almost logical to make investments in the Transmission System, which plays a fundamental role for this purpose. In this context, this work analyzes the variants related to the execution of works at the 500 kV level provided for in the ANDE Master Plan, considering the hypothesis that in said renegotiation the terms of purchase and sale of energy are changed. The evaluation was carried out considering 54 energy marketing strategies and reliability criteria. For the marketing analysis, income from energy transfer, the assumption of energy sales and changes in terms in the Treaty were considered. Likewise, for the reliability analysis, the simple contingency criterion was applied. The results reveal that, by advancing the execution time of some works, the economic performance of the SIN can be improved by up to 2.57&, compared to what was planned by ANDE. Furthermore, from a reliability point of view, an increase in the security of electricity supply has been observed. Therefore, considering the proposed approach, the ANDE Master Plan can be optimized, in order to have greater flexibility for the 500 kV works and greater robustness for the SIN, in order to be able to comply with future energy transaction commitments and obtain greater economic benefits.