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Maybe you want to say VCXO.
XVCO doesn’t exist yet in electronics terminology.
Just replacing an L with a crystal is not enough to get a good Variable Crystal Oscillator.
Now depends by the frequency of the crystal, by the crystal cut, and not to the last by the oscillator type. From what I know, with Butler VCXO oscillator you get the most ppm variation of the frequency.
Hard to tell you just from a basic oscillator schematic.
If you have all the transistor models run a simulation, replace the L with a crystal and see what variation in ppm you get.
Generally parallel tank configurations get lower ppm variation than series tank X-tal oscillator.