Overview
AR-57 is a buffing SMG.
AR-57’s Skill has a 2/3 uptime and a fairly low multiplier. The Evasion buff will almost never happen unless you kite her away from the other Dolls. She needs to be in Position 5 to hit the entire backline, but since she’s worse than an actual HG at buffing and only has SMG stats without a defensive Skill in this position, she shouldn’t be used as a main tank. If you put her on Position 8, she only hits 2 of the backline Dolls and only one DPS in a standard formation. The only interesting part of AR-57 is her very low CD, but if you want constant buffs, there are far better Dolls than her available.
Overall there is simply no reason to use AR-57 and as such, she is not recommended.