Generalized Yes to your question.
AVCHD (MP4 AVC/H.264) is a video compression which is supported by Premiere Elements 12, except when the AVCHD video compression has a file extension (wrapper format) of AVI. An AVCHD.mts file (AVCHD video compression with the .mts file extension - wrapper format) would be expected to be compatible with Premiere Elements 12.
But I will ask this...is your Premiere Elements 12 running on Windows or Mac computer?
Do you actually have Premiere Elements 12 at this time or are you just thinking about using it for editing some AVCHD.mts footage?
Lots of details go into the success or failure of a project.
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