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SurveyJS
Open-Source JSON Form Builder to Create Dynamic Forms Right in Your App. With SurveyJS form UI libraries, you can build and style forms in a fully-integrated drag & drop form builder, render them in your JS app, and store form submission data in any backend, inc. PHP, ASP.NET Core, and Node.js.
Of course, you could also go even further and hand craft a slide deck to hit the specific beats you want to cover. You could take the Mahjong Picture Guide as inspiration for what you want to put together. If you don't like their aesthetic or have a different idea of what you want to show in mind, then you could make use of free resources like the FluffyStuff Riichi Mahjong Tiles repository to build the examples that you want to show. It's a lot more work than either of the two earlier approaches, but you can know for certain what you will be showing your audience.
I will throw in another vote for Autotable, if you don't mind zipping around the table to play each hand. It's all manual, so if you don't plan on having other people around the table, you'll need to handle it all yourself. This could be good if you plan on trying to teach your audience how to play.