I dont think it has any incompatibilities but I can't be certain obviously. Mayar is correct in how to create the tems but I will also be implimenting it into military and police station loot pools with the next update

For anyone who comes along later and needs help figuring out how to use this mod:
There's a recipe to create a module that you can wear that adds the two slots. There is also a module you have to craft to hold the flashlight which you can then attach to the new hotbar slots. The other module's second slot holds the radio no problem.

any incompatibilities?

Is this mod known to be incompatible with anything?

Ah, the flashlight on shoulder looking good, it make more sense than put on belt from other mod

@Quilava Added a couple screenshots to show what the hotbar addition looks like when equipped- as well as the flashlight module and where it shows on the playermodel when equipped.

Would be great if you show us some ingame picture of the slot, also may i ask if radio slots can hold music device? Need that one for True Music player