ECWID to DEAR sync through Zapier

Hi there, I'm trying to sync order from ECWID to DEAR through Zapier.

I want to put these (mentioned below) from ECWID under the "Additional Charges and Services" in DEAR but I don't see a field for this in the Zapier. Is this Zapier issue?

What I want to map:

1. Discount (since ECWID discount is per order, and DEAR discount per item line, I try to map the order discount to DEAR as "Additional Charges and Service)

2. Shipping fee (also map from ECWID to DEAR as "Additional Charges and Service")

I understand DEAR has native sync with Shopify (I believe Shopify order fields are structured similar to ECWID). I am wondering how the mapping functions, and if it is possible for us to map these fields from ECWID to DEAR with Zapier.

If anyone has similar experience or can help, I'd appreciate it. Thanks.