Hi,

You don't want to re write the field entirely. Suppose if we have a field like this in base module:

class ProductTemplate(models.Model):
    _name = 'product.template'

    name = fields.Char('Name', index=True, required=True, translate=True, track_visibility='onchange')

And in the custom module if we want to change the string of the field(you can do it in xml where the field is defined with string=""),  do it like this,

class ProductTemplate(models.Model):
    _inherit = 'product.template'

    name = fields.Char(string='New Name')

For more info: https://www.youtube.com/watch?v=ZrCN3L0oAKE

Thanks