How to change existing shapes to BPMN 2.0 without redrawing

Hi Alexander thanks for posting in the Lucid Community! You're correct about the following functionality:

• The Change Shape ability is available only within a certain shape library not between libraries and is only available for specific common shape libraries such as Flowchart shapes. 
• The abilities within the right panel are specific to the shape library you're using - the BPMN 2.0 functions as shown in the screenshot below are specific to BPMN shapes while org chart tools are available only to org chart shapes etc. This is why these BPMN options are not available for your regular flowchart shapes.

Unfortunately it's not possible to find/replace or convert from one shape type to another across libraries. I certainly understand how that would be use though and especially impactful for your work here. I've logged this feedback for review by our development team which utilizes requests like these when prioritizing improvements to Lucidchart. If you have additional detail or use case context that you'd like to share we'd love to hear more via this thread or our feature request form. I'm so sorry for the inconvenience and thank you again for your feedback here!

I would love to understand what functionality the BPMN 2.0 tools are offering that you'd like to incorporate into your flowchart. There might be a different way we can incorporate it with another tool!