When I shoot the Kaiser plano without negatives, the exposure meter proposes 0,2 seconds (average grey and f/8 at 100 ISO) which means that I get exposure times of more than one second with a negative. I’ve never had any issues with motion blur with the self-timer set to 2 seconds and a mirrorless camera attached to a good stand like shown with a DSLR: Let's see your DSLR film scanning setup! - #56 by Digitizer
I’ve also used a “reversed” setup, where a lamp shines from above to the camera pointing up: Let's see your DSLR film scanning setup! - #35 by Digitizer
This setup provides ample light, only limited by the wattage of the bulb I install. It’s speciality bulb though, which means that it’s expensive, gets really hot and has a CRI of 100.
My third setup is still sleeping and waiting to get a device for the negative holder from the enlarger shown above: Let's see your DSLR film scanning setup! - #71 by Digitizer
While this setup has the most powerful backlight, it is uncomfortable for the eyes until the light is put in a box.
All in all, I have no problems with longer exposure times - if the setup is stable/rigid/heavy.