僕も君と同様楽しくない。

[ericaw]

English Translation

I’m not enjoying it in the same way you aren’t.

Could と be replaced with another particle, such as の or に?

[MsFixer]

@ericaw
No. 〜と同様 is a set phrase.

By the way, 僕も君と同様楽しくない sounds awkward and is more likely to be interpreted as “I am as a boring guy as you are”.

I would translate the English sentence as:

(casual) 君と同じで、僕も楽しめないわ。

(formal) あなたと同様、私も楽しめません。