Hey Jeff!
If it were just for Internal/OpenGL, the easiest way (I think) is Options > Element Attributes > Attribute Manager.
Switch to the Materials tab, click on the texture column heading to group all materials with textures together and clear the texture field.
Sadly, this will do nothing for LightWorks AFAIK ... you would have to go into Material settings and one by one click the 'match with internal' button... or, if materials were customized already for LW, look at each material in the LW settings tab and clear the texture there.
😞
If you're fortunate to not have TOO many materials in use, the checkmarks in Attribute Manager will at least let you see (even print) a list of which materials you need to edit for LW.
If this is something that you anticipate happening a lot, you can go through the laborious work of clearing all of the LW textures and save that set of materials via Attribute Manager as an AAT file. In the future when you have this need, you can open that AAT file and overwrite all of your existing materials (after backing them up with Att Mgr). You can then easily switch back to the textured materials the same way.
Hope somebody else knows a magic way to do this without so much work...
Cheers,
Karl
One of the forum moderators
AC 28 USA and earlier • macOS Sonoma 14.7.1, MacBook Pro M2 Max 12CPU/30GPU cores, 32GB