The first tool you should check out is FormulaGenerator. This AI-powered tool not only generates Excel formulas and VBA automations, but also checks for errors, explains how it generated the code, and offers a service called AnswersBot for asking spreadsheet questions. FormulaGenerator can be used as a web app or as a Google Sheets extension, and offers a free tier and a Premium Membership that costs $4.99/month and scales up as needed.
Another good option is ManyExcel, which offers an AI Formula Generator, Regex Generator and Script Generator for VBA automation. It can be used with both Excel and Google Sheets, and offers a free plan with limited use and a Pro plan for $5/month for unlimited formula and script generation.
If you want something more complete, you might want to check out Formula Bot. This tool can translate text into a variety of formats, including VBA scripts, and offers tools for data analysis and automating tasks. Formula Bot offers several pricing tiers, including a Free Forever option, so it should be useful for a variety of needs and budgets.