I gave this a quick try and it seemed to work just fine.
Steps:
1) I updated my OBS installation to OBS 28.1.2
2) I downloaded and ran the OBS<>Spout plugin
https://github.com/Off-World-Live/obs-spout2-plugin/releases/download/v1.5/OBS_Spout2_Plugin_Install_v1.5-obs28.exe3) I loaded a project into Magic, then enabled Spout output (
Window>Magic Window Options>Spout Output)
4) I confirmed Spout v2 was selected (
Window>Magic Window Options>Use Spout v2)
5) I started OBS, clicked
+ in the
Sources panel then selected
Spout2 Capture6) I clicked OK on the
Create/Select Source popup window
7) A properties window opened for Spout2 Capture, displaying my Magic output. I set
Spout Senders to
Magic Main Sender and clicked
OK8) My Magic output appeared in the OBS preview window, but it was zoomed in and there was a red box around it.
9) I set OBS to match my Magic project's resolution, and the full Magic output was shown in the OBS preview, without any red box
EDIT, sending transparency from Magic as well:10) I sent Magic's output with an alpha (transparency) channel (
Window>Magic Window Options>Send Alpha Channel)
11) In OBS I changed the
Spout2 Capture properties, setting
Composite Mode to
Premultiplied Alpha12) I added an image to the OBS
Sources panel, then dragged it below the
Spout2 Capture source. The image was then visible in the transparent regions of my Magic output.