It's possible, but it would have to be a built-in feature of the DAW to be convenient, and could seriously compromise performance even if optimized. Let's assu

It's possible, but it would have to be a built-in feature of the DAW to be convenient, and could seriously compromise performance even if optimized. Let's assume an ideal implementation where there is only one process per architecture. Take a 100 track project with two plug-ins per track (say, compressor and EQ). If the compressor is x86 and the EQ is ARM, that's 200 context switches per audio period. That makes it impossible to run at small buffer sizes. A very smart flowgraph implementation could attempt to batch everything into the minimum number of context switches, but that has other problems with threading. It's very hard to get this perfect. This solution works fine for when you just have a few straggler plug-ins of the wrong architecture, but it would still require quite complex engineering by the DAW to make it work transparently to the user. Consider, for example, that the plug-in UI needs to embed in the DAW across a process boundary.