Congrats on thinking proactively to make your organization more efficient and coming up with an actual solution!
A good way to approach this objectively is to tie your recommendation to your company's corporate goals / initiatives / core values --- which relate to automation/process improvement/efficiency. By doing that, you can diasarm your colleagues on your intent. You should also seek executive sponsorship / leadership support with your manager or other leader that is close to the corporate initiative that relates to your automation idea.
Use a tops down (leadership support) and bottom up (grassroots approach tied to company goals). Good luck!