eMMC and M.2 as one logical drive

Hello. Before I purchase eMMC or M.2 SSD I wanted to check if it is possible theoretically or practically to have LVM on both eMMC and M.2. I am not sure I use a correct term. So I want to have eMMC and M.2 as one single logical drive. Should it be possible to configure them like this assuming boot is done from SPI or eMMC?

While I generally don’t like setting up storage like that, since your filesystem is only as reliable as the least reliable device, and fails when the first of the multiple devices fail, but as far as being technically possible… sure. It absolutely is possible. And it doesn’t matter what you boot from.

Technically possible but I don’t suggest it as @lbdroidman points out.