Hello Enrico,
No, there is no single pre-programmed, orderable FS26 part number that natively supports both MCUs.
Regarding the part number suffix (for example E4 in MFS2633HMDE4AD), this suffix represents a specific OTP/programmed variant. It is not by itself a generic MCU compatibility field. The actual base device capability is mainly defined by the FS26xyB/FS26xyD portion of the part number, which defines the silicon feature set (for example VCORE capability, number of trackers, LDT/FS1B presence and ASIL B vs ASIL D), while the suffix identifies the exact programmed version.
BRs, Tomas