@Hassan: For widened spreads (slippage) during extraordinary conditions such as high-impact news, you can ask directly to the customer service (CS) of brokers XM and Exness. Or you can also observe in the account type details of the two brokers.
From the information I received, at broker XM there are 4 types of accounts namely micro, standard, ultra low, and shares account. Micro, standard, and ultra low accounts for forex trading do not have transaction commissions. While for the shares account there is a commission, but this type of account is specifically for stock traders.
Meanwhile broker Exness has 5 types of accounts namely standard account, standard cent, pro, zero, and raw spread. Standard, standard cent, and pro accounts have no commission, while the zero account has a commission of $0.05 per lot and the raw spread account has a commission of $3.5 per lot.