How to reproduce 

grass stone bug:

 go to the seed: 5065972378046467357

and go to the ubication using :  /tp @s 88 64 -668

grass grass path Bug:

go to seed: 5065972378046467357

and go to the ubicacion using /tp @s 244 67 -784

grass Sand Bug

go to seed 5065972378046467357

and go to the ubication: /tp @s 223 63 -767