I am moving my website to Smugmug and it is recommended that images should be uploaded at full size JPEGs to allow different display resolutions and allowing prints to be produced from the the images (not sure about this bit yet, but!)
Normally I web sharpen using TKActions Panel v5's Web Sharpener, but this is when I am resizing the image down. What I am wondering is what is the best way to output sharpen for Web when the image isn't being resized ? Do people recommend exporting in LR or a sharpening approach is PS ?
If someone else, like Smugmug, is going to resample the image (at different scales), it's probably better if you do relatively little output sharpening on your large source image. Any sharpening you do, may increase the chance of aliasing artifacts being created by their downsampling algorithms. Only if they also offer an "Original size" option, you could optimize for that size, but with some restraint.
Maybe you can ask if they apply any sharpening after resampling (hint: they should). If they do, you could even add a tiny bit of blur to the source image, depending on how well their sharpening algorithms respond to that.
If you have very good output sharpening skills/tools, you could apply them to the full size source image, because they will probably not create significant issues downstream, but a lot depends on what happens during and after resampling.