The idea behind the Offset-G is that the G keys are slightly pushed forward so fingers can reach them more easily. In Inline flutes, the G keys align in line with the other flute holes. With such a flute, the left-hand ring finger might need to stretch a bit more, especially if it's a flute with ring keys, and the finger needs to precisely rest on the key. In terms of sound, there's no noticeable difference whether you play a flute with Inline or Offset-G.
Many French flute makers still craft Inline flutes, partly due to tradition and also because they find the design more appealing. So, if you want a ring key flute with Offset-G, you might need to consider a different manufacturer.