v.split
v.split.vert - Split lines to shorter segments by max number of vertices.
Vector (v.*)
QgsProcessingParameterVectorLayer|input|Input lines layer|1|None|False
QgsProcessingParameterNumber|vertices|Maximum number of vertices in segment|QgsProcessingParameterNumber.Double|10|False|None|None
QgsProcessingParameterVectorDestination|output|Split by vertices