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Earthquake direction can differ from a building's major axis, potentially resulting in heightened seismic response in structural elements. Conversely, plan irregularities, including L and T-shaped building configurations, lead to torsional floor rotations that concentrate seismic demand in specific areas, often resulting in severe structural damage. This paper delves into the influence of earthquake direction on irregular L-shaped and T-shaped tall steel buildings, employing nonlinear time history analysis via OpenSEES. The study investigates incident angles ranging from 0 to 180 degrees, with 15-degree increments, concentrating on parameters such as displacements, drift ratios, and acceleration amplifications. The methodology involved creating numerical models using OpenSEES platform. Two distinct building shapes, L and T configurations, with 22 stories each, were analyzed. The models incorporated uniform architectural layouts, column distribution, and bracing systems. Both static and dynamic loading conditions were considered, with earthquake data adapted to the region's seismic characteristics. The findings reveal that incident angle variations significantly impact seismic responses in irregular structures. Critical incident angles vary depending on building design. Buildings with symmetry about one axis exhibit lower deviations from the reference angle. Further research is needed to develop empirical formulas for incident angle effects in structural analysis and to predict critical incident angles for different building types. [ABSTRACT FROM AUTHOR]