Do you know an eq plugin with low shelf above -50Db or more – Effects Forum

FabFilter Pro-Q 3, you can set custom slopes (including 12dB/oct) and specific crossover frequencies. The gain range goes as low as -96dB, which easily allows for the deep cuts you’re looking for.

DMG Audio EQuilibrium is another highly flexible EQ that allows you to create very specific custom curves. It has a deep cut range and can handle the kind of precision you need for matching the Xone EQ.

Waves F6 Floating-Band Dynamic EQ allows for adjustable frequency bands with a range that can easily handle cuts beyond -45dB. It’s also a dynamic EQ, meaning you can make the bands respond to the input signal, which might be useful for DJ-style effects.

TDR Nova GE, while primarily a dynamic EQ, it offers extensive controls over each frequency band, including very deep cuts and flexible filter settings. The notch can go deep enough for what you’re looking to achieve, and it provides great flexibility in band placement.

Since you already have the EQ curve from Wave Q-Clone, you can use that as a reference to match the curve in the plugin you choose.