Replace & Destroy

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Commands in order of execution:
/scoreboard objectives add <OBJECTIVE> dummy
/fill <X1> <Y1> <Z1> <X2> <Y2> <Z2> double_plant 0 replace <YOUR BLOCK>
/scoreboard players set @e[type=Item] <OBJECTIVE> 1 {Age:0s,Item:{id:minecraft:double_plant}}
/execute @e[score_<OBJECTIVE>=] ~ ~ ~ setblock ~ ~ ~ <YOUR BLOCK>
/execute @e[score_<OBJECTIVE>=] ~ ~ ~ setblock ~ ~ ~ air 0 destroy
/kill @e[score_<OBJECTIVE>=]
/scoreboard objectives remove <OBJECTIVE>
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