Well if you do this the effect of the sound will be gone. You won't be able to tell the different

Are you talking about Dolby Atmos up-firing speaker modules? If yes, then understand that they don't work very well.
The correct way to implement height speakers is to have them as close to the ceiling as possible if in-ceiling speakers isn't an option for you. So of course, the height speakers MUST be placed higher than your surround speakers.

Too bad, how about Front Height + Front Wide?

No problem on the height, the problem is I have constrain to put my surround speaker down to the ear level which is below the atmos speaker 

The same rules apply

Wait I don't understand... putting the surround speakers to ear-level is EXACTLY what Dolby recommends everyone to do in their setups. Not saying it's the best, but that's the correct guideline. So what's the problem?

What really matters most is that the height speakers MUST always be higher than your bed layer speakers by at least 6 ft., generally speaking. Of course different rooms, different measurements.
*EDIT*

In this case I might consider to move the surround to the back so that it can lower to the ear level

Where are you mounting your height speakers? On top of your current L/R surround but near the ceiling? It's difficult to give a recommendation if you don't list down your room dimensions.

This is my current 5.1 surround placement, red box

This is my current 5.1 surround placement, red box

To put it very simply, lobing refers to the issue where speakers of MTM design has an issue where woofers can cancel out one another causing dialog intelligibility to become an issue when the listener is sitting off axis (meaning not directly infront of the center speaker).

Not a big issue if you only have 1 MLP, but if you have a wide room and have many seats, you should choose a WTMW center speaker design or just buy a vertical bookshelf and use that as the center channel instead (of which then you would absolutely want to match it with your L/R speakers).

Angle adjustment is not a feature. You can just DIY yourself by buying a pack of door stoppers (if speaker feets are not an option) and get the exact angle you want for any kind of speaker.

Alright, your surrounds are too high and adding in the height speakers will have a negative effect on your overall system.

Is it impossible to place your surround speakers 5 ft. lower but remain at the same side positions? Rear placement for surround speakers can work, but you need to position them properly otherwise you may hear a gap between the front and sides during panning effects.

Lobing usually happened to TM. MTM Will not cause lobing , in fact , MTM eliminate those lobing.

I can only lower down 1 side of the surround only, the other side wall very far away. How to position the surround at the back?

This is my current 5.1 surround placement, red box

How to position the surround at the back?

Is your surround monopole or dipole/bipole?

If monopole, just place it behind you, pointing directly forward. The distance between them, that you will have to measure out yourself because you didn't provide any info on your room dimensions or measurements.

are you planning for 7.1?

Monopole, my HT area 20ft long and 13ft wide. If add only front height speaker to my current setup, is that advantage for DTS-X sound?
I'm planning for 5.1.4

Monopole, my HT area 20ft long and 13ft wide. If add only front height speaker to my current setup, is that advantage for DTS-X sound?
I'm planning for 5.1.4

Oppo UDP-203 released
http://www.oppodigital.com/blu-ray-udp-203/