intelligence, imperial
睿 centers on deep, penetrating insight: intelligence that sees clearly and makes wise judgments. The imperial sense is a specific application of that wisdom to ruling.
睿 is thought to combine 目 (eye) with elements suggesting depth or clarity, conveying the idea of penetrating vision or insight. The exact historical development of the upper components is uncertain.
The bottom 目 is an eye, and the upper part looks like a covering or a deep well. Picture an eye peering into a deep well and seeing clearly what others miss: that penetrating sight is intelligence.
For エイ, imagine a wise emperor named A (エイ) who rules with deep insight. His name A cues エイ, and his imperial wisdom matches the kanji's meaning.