Start Crossover and open Run Command. Pick the bottle you want to enable anti-aliasing in, and in Run Command run regedit.
Then proceed to HKEY_CURRENT_USER>Control Panel>Desktop and set (or create the key if it doesn't exist) to:
FontSmoothing=2 (string key)
FontSmoothingType=00000002 (dword key)
FontSmoothingGamma=00000578 (dword key)
FontSmoothingOrientation=00000001 (dword key)
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