In her right hand, as if to say 'this is a magical-girl item,' was a suspicious-looking rod.
Literal
Right-hand [in-には], clearly, 'magical-girl item [copula-です]' [as-if-to-say-と言わんばかりの] suspicious-looking rod [subject-が] gripped was.
言わんばかり ('as if about to say') uses classical 言わん (= 言おう, volitional of 言う) + ばかり ('on the verge of'). 怪しげ uses the ~げ suffix for 'having an air of.' 魔法少女 ('magical girl') is the anime genre featuring young girls with magical powers and transformation items. いかにも ('clearly, unmistakably') reinforces the obviousness of the rod's magical-girl aesthetic.