Soil pipe join fall

The entry to the soil pipe on the outside of my house is about 200mm away from the corner of my bathroom. I need the soil pipe to run as close to the wall as possible as the toilet is a few meters away inside the bathroom so I was going to put two 45 joins to move it closer to the wall. This part I think is fine to do? My question is, can the two 45 joins fall 50mm from one end to the other to allow a 40mm waste pipe to sit underneath or will this risk blockages inside that bend? The 40mm pipe already goes through the wall in that position so I don’t think I can move it.