更新：
好吧我试着把家里老掉牙的奶奶电脑请出来了，在上面完成了刷机过程。
确保安装了驱动，确保解锁了BootLoader，能在fastboot模式连接上电脑，我只是想刷入rec结果遇上了麻烦
尝试了adb命令，结果如下：
pc端反馈：
E:\adb>fastboot oem help
…
(bootloader) config…
(bootloader) hw…
(bootloader) partition…
(bootloader) blankflash
(bootloader) fb_mode_set
(bootloader) fb_mode_clear
(bootloader) bp-tools-on
(bootloader) bp-tools-off
(bootloader) qcom-on
(bootloader) qcom-off
(bootloader) unlock
(bootloader) lock
(bootloader) get_unlock_data
(bootloader) cid_prov_req
(bootloader) off-mode-charge
(bootloader) read_sv
OKAY [ 0.036s]
finished. total time: 0.037s
E:\adb>fastboot getvar all
getvar:all FAILED (remote: unknown command)
finished. total time: 0.015s
E:\adb>fastboot getvar all
(bootloader) a: not found
getvar:all FAILED (remote failure)
finished. total time: 0.018s
E:\adb>fastboot oem help
…
FAILED (remote: unknown command)
finished. total time: 0.019s
E:\adb>fastboot oem help
…
(bootloader) config…
(bootloader) hw…
(bootloader) partition…
(bootloader) blankflash
(bootloader) fb_mode_set
(bootloader) fb_mode_clear
(bootloader) bp-tools-on
(bootloader) bp-tools-off
(bootloader) qcom-on
(bootloader) qcom-off
(bootloader) unlock
(bootloader) lock
(bootloader) get_unlock_data
(bootloader) cid_prov_req
(bootloader) off-mode-charge
(bootloader) read_sv
OKAY [ 0.047s]
finished. total time: 0.048s
E:\adb>fastboot oem help
…
FAILED (remote: unknown command)
finished. total time: 0.025s
E:\adb>fastboot flash recovery “E:\adb\nash rec.img”
(bootloader) par: not found
sending ‘recovery’ (34224 KB)…
(bootloader) Failed to get the number of bytes to download
FAILED (remote failure)
finished. total time: 0.037s
E:\adb>fastboot flash recovery “E:\adb\nash rec.img”
(bootloader) m: not found
sending ‘recovery’ (34224 KB)…
FAILED (remote: unknown command)
finished. total time: 0.041s
E:\adb>fastboot oem help
…
(bootloader) config…
(bootloader) hw…
(bootloader) partition…
(bootloader) blankflash
(bootloader) fb_mode_set
(bootloader) fb_mode_clear
(bootloader) bp-tools-on
(bootloader) bp-tools-off
(bootloader) qcom-on
(bootloader) qcom-off
(bootloader) unlock
(bootloader) lock
(bootloader) get_unlock_data
(bootloader) cid_prov_req
(bootloader) off-mode-charge
(bootloader) read_sv
OKAY [ 0.064s]
finished. total time: 0.065s
E:\adb>fastboot oem help
…
FAILED (remote: unknown command)
finished. total time: 0.041s
E:\adb>fastboot flash boot “E:\adb\nash rec.img”
sending ‘boot’ (34224 KB)…
(bootloader) Requested download size is more than max allowed
FAILED (remote failure)
finished. total time: 0.049s
手机端反馈：
尝试刷入底包也是出现此类问题
手机用起来一切正常，但是我真的想换了rec用体验其他系统。大佬们帮帮我吧