Panasonic GH5 has a Micro Four Thirds lens mount and currently there are 107 native lenses available for this mount.
GH5 also has a sensor based image stabilization system which means that all of these lenses will be stabilized when used on GH5.
Since Panasonic GH5 has a Four Thirds sensor, it has a focal length multiplier of 2x so you have to multiply lenses original focal length with this multiplier to find the Full Frame equivalent focal length of the lens when mounted on GH5.
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Panasonic GH5 Lenses with Image Stabilization
Panasonic GH5 Lenses with Weather Sealings