Chips always show USD amounts. If depositing in another currency, the summary shows how much you'll be charged in your local currency. Simple and consistent.
Chips show amounts in the selected deposit currency (PLN/EUR). The user thinks in their own money. Summary shows how much USD they'll receive in their balance.
Each chip shows both currencies stacked. Maximum transparency - users see exactly what they pay and what they get at every step. Best for trust.
User picks their mental model: enter amounts in USD or in their local currency. The "other" currency is always shown as a live conversion. Most flexible but adds an extra UI element.
Based on Variant C with an expandable promo code section. Shows a banner when a code is applied, and the bonus amount appears in the summary breakdown.