。
She likes basketball just as much as tennis.
Literal
She [topic-は] tennis [the same way as-と同様に] basketball [also-も] likes is.
~と同様に ('in the same way as / similarly to') is the formal/written counterpart of the casual ~と同じように, 'just like.' Both compare two things along a stated dimension. 同様 (dōyō, na-adjective/noun, 'the same way, similarly') is a Sino-Japanese alternative to 同じ (native, 'same'); the に turns it into an adverb. The も on バスケットボール continues the additive 'also' logic — once tennis is established as a like, basketball joins the set. バスケットボール is a loanword; clipped to バスケ in casual speech.