On the FaceBook search page for '16mm modular' most of the links are for modular furniture and wot not.
Only one link had a 16mm scale, 32mm gauge modular layout at Statfold Barn. The video is below.
I believe the layout in the video is using the 'Association of 16mm Narrow Gauge Modelers' modular design as previously mentioned.
Modular Layout Standards - Association of 16mm Narrow Gauge Modellers
The 16mm NGM modules specify a nominal radius of 169.7cm with other tracks at 15cm spacing. A smaller radius of 139.7cm is also used for tighter layouts.
I suspect a system for 45mm gauge G scale use may be more beneficial using LGB set track / point radius as nominal. Other tracks at the same spacing of 15cm then being compatible with the 16mm NGM system with the exception of mixing curve modules because of the differing nominal radius.
The modular requirements for an R1/R2, R3 or R5 are completely different and none shall be mixed on the same module because the track spacing is not in increments of 15cm.
R1 and R2 could be on the same module using R2 as nominal. The R1 could be stepped in a little to give a spacing of 15cm from the R2 instead of 18cm as it is but close spacing with small radius could create issues with passing cars. The LGB track spacing geometry for smaller radius is closer to 18cm on curves.
https://www.lgb.de/fileadmin/media/lgb/service/FAQ/LGB-Technik-Tipp-201-LGB-gleissystem.pdf
These issues need to be considered if LGB track system is used on modules. As usual, the devil is in the details.