sexual love vs sexual activity

sexual love and sexual activity both are nouns.

Word	Noun	Adjective	Verb	Adverb
sexual love	Yes	No	No	No
sexual activity	Yes	No	No	No

As nouns, sexual activity is a hypernym of sexual love; that is, sexual activity is a word with a broader meaning than sexual love:

sexual love: sexual activities (often including sexual intercourse) between two people
sexual activity: activities associated with sexual intercourse

Other hypernyms of sexual love include sex, sex activity, sexual practice.

sexual love (noun)	sexual activity (noun)
sexual activities (often including sexual intercourse) between two people	activities associated with sexual intercourse
a deep feeling of sexual desire and attraction