My sailplane mix for DX6i radio:
Sure. The dx6i only has 2 mixes, but crow still possible you will just have full up or down movements.

YOUR RX:
-using a y harness with built in servo reverser on flaps
-ar6200 full range
Aux1 -left sailplane aileron
GEAR - put your y harnessed servo reverser here for flaps of your plane
RUD -rudder
ELE -elevator
AILE -right sailplane aileron
THRO -esc
BATT -rx battery or bec

MIX 1

AILE > RUDD ACT
RATE L + 75% R +75%
sw mix trim act



MIX 2

GEAR > AILE ACT
RATE L + 0% R +0%
sw elev d/r trim act

-

WINGTAILMIX
DUALAILE ACT

-

FLAPS

NORM < 0 0
LAND ↓66 ↑23

What can you do with this?
normal flight: ail - thro - elev - rudd
flaps down: gear switch
airbrake: both ails rasied (ele DR switch)
crow: ails up and flaps down
REMEMBER FOR CROW YOU HAVE TO HIT GEAR SWITCH AND ele DR SWITCH TO INITIATE CROW.


THIS IS ALL I COULD FIGURE OUT FOR THE DX6i AND USE IT ON MY SAILPLANE AND WORKS VERY WELL.
PLEASE IF YOU HAVE MORE OR ANYTHING TO ADD ON TO THIS SETUP PLEASE POST!