How to work with a local copy when not remuxing?

My files are on a lan (unraid). Remux is turned off since all the input is mkv, and it has zero benefit for this task. Well, it has one benefit that i’d like to get back - the remuxed file is created locally in the mcebuddy temp directory.

Without remuxing the program is working the file directly from unraid, which is fine… most of the time. When unraid drives get bogged down, like when the mover flushes a large amount of files off the cache drive, mcebuddy conversions sometimes slow down, sometimes hang and sometimes error out. I can replicate this behavior by manually flushing the cache drive. The more files, especially smaller files, the worse the effect. This is more of an unraid/networking issue, but one i can easily get around by copying the file to /temp and working/deleting the file locally, just like remuxing does.

Is there an easy way to do this from the gui/config file or an advanced command? Is this something that will require messing with scripts and custom commands ?