The sobriquet, Haosou, can be identified as the official, Yang Yisun (1812-1881) who is recorded as a Juren, having passed his prefecture examination in 1843, and was a well-known seal carver. Cf. Zhongguo Meishujia Renming Cidian, Shanghai renmin chubanshe, 2003, p. 1181; where it is noted that the sobriquet, Haosou was adopted during Yang Yisun's latter years.
The couplet may be translated as:
The cinnabar imparts a measure of beauty,
repeatedly used by a deft hand at a passing pleasure.