Is there a palace in Luoyang that can compete with Xi Daming Palace?

Yes, Wei Zi is one square kilometer bigger than Daming Palace.

Weizi Town, also known as Wei Zi Palace, is the main hall, political center and national symbol of Sui, Tang and Wu Zhou empires in Luoyang City and Miyagi City of Sui and Tang Dynasties. It was built in the northwest corner of Luoyang City in the Sui and Tang Dynasties (605) and completed the following year. In the sixth year of Emperor Taizong's Zhenguan reign (632), in the first year of Wu Zetian's Guangzhai reign (684), Luoyang Palace was called Taichu Palace. Since its establishment, it has become the ruling place of Sui Dynasty, Tang Dynasty, Wu Zhou, Hou Liang, Later Tang Dynasty, Later Jin Dynasty and Northern Song Dynasty. It has existed for more than 530 years and is the most used palace in China history.

Weizi Town was the most magnificent palace group in the world at that time, and its shocking architectural form influenced the palace buildings in East Asian countries. Especially in the era of Wu Zetian, buildings such as Tang Ming and Paradise made it unique and became a miracle of the world. Weizi Town covers an area of about 4.2 square kilometers, which is six times that of the Forbidden City in Beijing in Ming and Qing Dynasties. There are more than 3,500 other halls, tables and halls in the palace, and there are more than 9,990 districts in the palace.