It's mostly ostheer job to deal with emplacements but okw also has some pretty good units for this. The most obvious choice is setting the battlegruppe HQ just outside of mortars range so you could bombard them with LeIG (attack ground ofc) and reinforce them when needed. This usually deals well with emplacements but if you would like to speed up the process you can also use cloaked raketenwerfers and stuka zu fuss but remember to use them when brace is realoading - they will have to brace not to get killed really fast by the LeIG, you wait unitll it stops and fire AT guns or stuka. Stuka also is great at killing repairing royal engineers.
If you manage to kill all bofors emplacements so you can get a little closer, volkgrenadiers have great incendiary granade that deals tons of damage to emplacements and lasts longer than brace.
Hi. I play wher. 2v2 . 2 brits make me sick. They build mortars I try burn it with hf but they build bofors too early. Than all mortas fall my head. I lost many mans. Than I try stuka and stuka bomb. skill no damage to brits units. They allways repair...