there are PE cutters availiable similar to sprue cutters for plastic but they are expensive.
I use a sharp curved blade (#23) on a ceramic tile and just roll the blade over the PE sprue line. I then trim it closer if need be with this and finish with a fine needle file.
to bend the PE I use a flat steel rule and a one sided razor blade. I would love a PE folder but once again as I do not use a lot of it now it is uneconomical for me to part out the cash. However if I had money to spare this tool is what I would buy. My preference being the 'Hold & Fold' brand.
For resin the only extra tool I have is a razor saw. This comes in handy for trimming the casting blocks off. Other then that my plastic tools do as good a job on resin as they do on plastic.
Hope this helps