Freeware - Ghost Note Audio Spectrum Thief VST Plugin

https://ghostnoteaudio.uk/products/spectrum-thief

Spectrum Thief is an EQ-matching plugin that can import and export impulse responses. Great for capturing the frequency response of speaker cabinets, or creating adjustment filters to tone-match your guitar tone (or even a full mix), to a reference sound. The plugin is FREE and requires no authentication or registration, so grab your copy!