Bing chat：

含沙射影 (hán shā shè yǐng) means “to attack someone by insinuation” or “to slander someone secretly”.

指桑骂槐 (zhǐ sāng mà huái) means “to scold someone by pointing to a mulberry tree and cursing a locust tree”. It is used to describe a situation where someone is scolding another person but is actually referring to a third person .